multiple assignment in js

Multiple Variable Assignment in JavaScript

• JavaScript Howtos
• Multiple Variable Assignment in …

Use the = Operator to Assign Multiple Variable in JavaScript

Multiple variable assignment using destructuring assignment with fill() function in javascript.

This tutorial explains multiple variable assignments in JavaScript because variables are the most important part of our coding.

Sometimes, we have to do many variable declarations and assignments as they have the same value. How? Let’s understand.

Assume we have variable1 , variable2 , and variable3 and want all three variables to have a value of 1 .

They seem equivalent, but they are not. The reason is variables’ scope and assignment precedence .

The assignment operator is right-associative in JavaScript, which means it parses the left-most after parsing the right-most.

Let’s have another example to understand variable scope and assignment precedence .

Focus on the code and see that variable1 , variable2 , and variable3 are in function scope and local to the test1() .

They are not available outside of test1() method that’s why returning undefined . Here, var variable1 = 1, variable2 = 1, varialbe3 = 1; is equivalent to var variable1 = 1; var variable2 = 1; var varialbe3 = 1; .

Now, observe the test2() function. The variable1 is in function scope due to the var keyword, but variable2 and variable3 are leaking because they are not written with the var keyword.

They are globally accessible outside the test2() function. Remember that the variable declarations are hoisted only.

However, the precedence is right-associative which means var variable1 = (window.variable2 =(window.variable3 = 1)); .

Which Means the variable3 will be assigned to 1 first, then the value of variable3 will be allocated to variable2 , and lastly, the value of variable2 will be assigned to variable1 .

To avoid a variable leak in test2() , we can split the variable declaration and assignment into two separate lines. In this way, we can restrict variable1 , variable2 , and variable3 to test2() function scope.

The destructuring assignment helps in assigning multiple variables with the same value without leaking them outside the function.

The fill() method updates all array elements with a static value and returns the modified array. You can read more about fill() here .

Mehvish Ashiq is a former Java Programmer and a Data Science enthusiast who leverages her expertise to help others to learn and grow by creating interesting, useful, and reader-friendly content in Computer Programming, Data Science, and Technology.

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JavaScript multiple assignment

In JavaScript, you can assign multiple variables in the same line of code:

And you can also assign several variables together:

What just happened? Assignment is right associative (pairs from right to left), so you can think of the previous code as being the same as:

The right most pair is like an assignment when you forget to put the var keyword.

You can also think about var a = (b = 3) as:

Avoid creating global variables (window.a is a global variable). If you create global variables, you can create bugs when you use the same variable name.

What's the output?

What's the console output.

13 Variables and assignment

These are JavaScript’s main ways of declaring variables:

• let declares mutable variables.
• const declares constants (immutable variables).

Before ES6, there was also var . But it has several quirks, so it’s best to avoid it in modern JavaScript. You can read more about it in Speaking JavaScript .

13.1  let

Variables declared via let are mutable:

You can also declare and assign at the same time:

13.2  const

Variables declared via const are immutable. You must always initialize immediately:

13.2.1  const and immutability

In JavaScript, const only means that the binding (the association between variable name and variable value) is immutable. The value itself may be mutable, like obj in the following example.

13.2.2  const and loops

You can use const with for-of loops, where a fresh binding is created for each iteration:

In plain for loops, you must use let , however:

13.3 Deciding between const and let

I recommend the following rules to decide between const and let :

• const indicates an immutable binding and that a variable never changes its value. Prefer it.
• let indicates that the value of a variable changes. Use it only when you can’t use const .

exercises/variables-assignment/const_exrc.mjs

13.4 The scope of a variable

The scope of a variable is the region of a program where it can be accessed. Consider the following code.

• Scope A is the (direct) scope of x .
• Scopes B and C are inner scopes of scope A.
• Scope A is an outer scope of scope B and scope C.

Each variable is accessible in its direct scope and all scopes nested within that scope.

The variables declared via const and let are called block-scoped because their scopes are always the innermost surrounding blocks.

13.4.1 Shadowing variables

You can’t declare the same variable twice at the same level:

eval() delays parsing (and therefore the SyntaxError ), until the callback of assert.throws() is executed. If we didn’t use it, we’d already get an error when this code is parsed and assert.throws() wouldn’t even be executed.

You can, however, nest a block and use the same variable name x that you used outside the block:

Inside the block, the inner x is the only accessible variable with that name. The inner x is said to shadow the outer x . Once you leave the block, you can access the old value again.

13.5 (Advanced)

All remaining sections are advanced.

13.6 Terminology: static vs. dynamic

These two adjectives describe phenomena in programming languages:

• Static means that something is related to source code and can be determined without executing code.
• Dynamic means at runtime.

Let’s look at examples for these two terms.

13.6.1 Static phenomenon: scopes of variables

Variable scopes are a static phenomenon. Consider the following code:

x is statically (or lexically ) scoped . That is, its scope is fixed and doesn’t change at runtime.

Variable scopes form a static tree (via static nesting).

13.6.2 Dynamic phenomenon: function calls

Function calls are a dynamic phenomenon. Consider the following code:

Whether or not the function call in line A happens, can only be decided at runtime.

Function calls form a dynamic tree (via dynamic calls).

13.7 Global variables and the global object

JavaScript’s variable scopes are nested. They form a tree:

• The outermost scope is the root of the tree.
• The scopes directly contained in that scope are the children of the root.

The root is also called the global scope . In web browsers, the only location where one is directly in that scope is at the top level of a script. The variables of the global scope are called global variables and accessible everywhere. There are two kinds of global variables:

Global declarative variables are normal variables.

• They can only be created while at the top level of a script, via const , let , and class declarations.

Global object variables are stored in properties of the so-called global object .

• They are created in the top level of a script, via var and function declarations.
• The global object can be accessed via the global variable globalThis . It can be used to create, read, and delete global object variables.
• Other than that, global object variables work like normal variables.

The following HTML fragment demonstrates globalThis and the two kinds of global variables.

Each ECMAScript module has its own scope. Therefore, variables that exist at the top level of a module are not global. Figure 13.1 illustrates how the various scopes are related.

Figure 13.1: The global scope is JavaScript’s outermost scope. It has two kinds of variables: object variables (managed via the global object ) and normal declarative variables . Each ECMAScript module has its own scope which is contained in the global scope.

13.7.1  globalThis [ES2020]

The global variable globalThis is the new standard way of accessing the global object. It got its name from the fact that it has the same value as this in global scope (script scope, not module scope).

For example, in browsers, there is an indirection . That indirection is normally not noticable, but it is there and can be observed.

13.7.1.1 Alternatives to globalThis

The following global variables let us access the global object on some platforms:

• window : The classic way of referring to the global object. But it doesn’t work in Node.js and in Web Workers.
• self : Available in Web Workers and browsers in general. But it isn’t supported by Node.js.
• global : Only available in Node.js.

13.7.1.2 Use cases for globalThis

The global object is now considered a mistake that JavaScript can’t get rid of, due to backward compatibility. It affects performance negatively and is generally confusing.

ECMAScript 6 introduced several features that make it easier to avoid the global object – for example:

• const , let , and class declarations don’t create global object properties when used in global scope.
• Each ECMAScript module has its own local scope.

It is usually better to access global object variables via variables and not via properties of globalThis . The former has always worked the same on all JavaScript platforms.

Tutorials on the web occasionally access global variables globVar via window.globVar . But the prefix “ window. ” is not necessary and I recommend to omit it:

Therefore, there are relatively few use cases for globalThis – for example:

• Polyfills that add new features to old JavaScript engines.
• Feature detection, to find out what features a JavaScript engine supports.

13.8 Declarations: scope and activation

These are two key aspects of declarations:

• Scope: Where can a declared entity be seen? This is a static trait.
• Activation: When can I access an entity? This is a dynamic trait. Some entities can be accessed as soon as we enter their scopes. For others, we have to wait until execution reaches their declarations.

Table 13.1 summarizes how various declarations handle these aspects.

Table 13.1: Aspects of declarations:

• “Duplicates” describes if a declaration can be used twice with the same name (per scope).
• “Global prop.” describes if a declaration adds a property to the global object, when it is executed in the global scope of a script.
• TDZ means temporal dead zone (which is explained later).

(*) Function declarations are normally block-scoped, but function-scoped in sloppy mode .

import is described in “ECMAScript modules” (§29.5) . The following sections describe the other constructs in more detail.

13.8.1  const and let : temporal dead zone

For JavaScript, TC39 needed to decide what happens if you access a constant in its direct scope, before its declaration:

Some possible approaches are:

• The name is resolved in the scope surrounding the current scope.
• You get undefined .
• There is an error.

Approach 1 was rejected because there is no precedent in the language for this approach. It would therefore not be intuitive to JavaScript programmers.

Approach 2 was rejected because then x wouldn’t be a constant – it would have different values before and after its declaration.

let uses the same approach 3 as const , so that both work similarly and it’s easy to switch between them.

The time between entering the scope of a variable and executing its declaration is called the temporal dead zone (TDZ) of that variable:

• During this time, the variable is considered to be uninitialized (as if that were a special value it has).
• If you access an uninitialized variable, you get a ReferenceError .
• Once you reach a variable declaration, the variable is set to either the value of the initializer (specified via the assignment symbol) or undefined – if there is no initializer.

The following code illustrates the temporal dead zone:

The next example shows that the temporal dead zone is truly temporal (related to time):

Even though func() is located before the declaration of myVar and uses that variable, we can call func() . But we have to wait until the temporal dead zone of myVar is over.

13.8.2 Function declarations and early activation

In this section, we are using functions – before we had a chance to learn them properly. Hopefully, everything still makes sense. Whenever it doesn’t, please see “Callable values” (§27) .

A function declaration is always executed when entering its scope, regardless of where it is located within that scope. That enables you to call a function foo() before it is declared:

The early activation of foo() means that the previous code is equivalent to:

If you declare a function via const or let , then it is not activated early. In the following example, you can only use bar() after its declaration.

13.8.2.1 Calling ahead without early activation

Even if a function g() is not activated early, it can be called by a preceding function f() (in the same scope) if we adhere to the following rule: f() must be invoked after the declaration of g() .

The functions of a module are usually invoked after its complete body is executed. Therefore, in modules, you rarely need to worry about the order of functions.

Lastly, note how early activation automatically keeps the aforementioned rule: when entering a scope, all function declarations are executed first, before any calls are made.

13.8.2.2 A pitfall of early activation

If you rely on early activation to call a function before its declaration, then you need to be careful that it doesn’t access data that isn’t activated early.

The problem goes away if you make the call to funcDecl() after the declaration of MY_STR .

13.8.2.3 The pros and cons of early activation

We have seen that early activation has a pitfall and that you can get most of its benefits without using it. Therefore, it is better to avoid early activation. But I don’t feel strongly about this and, as mentioned before, often use function declarations because I like their syntax.

13.8.3 Class declarations are not activated early

Even though they are similar to function declarations in some ways, class declarations are not activated early:

Why is that? Consider the following class declaration:

The operand of extends is an expression. Therefore, you can do things like this:

Evaluating such an expression must be done at the location where it is mentioned. Anything else would be confusing. That explains why class declarations are not activated early.

13.8.4  var : hoisting (partial early activation)

var is an older way of declaring variables that predates const and let (which are preferred now). Consider the following var declaration.

This declaration has two parts:

• Declaration var x : The scope of a var -declared variable is the innermost surrounding function and not the innermost surrounding block, as for most other declarations. Such a variable is already active at the beginning of its scope and initialized with undefined .
• Assignment x = 123 : The assignment is always executed in place.

The following code demonstrates the effects of var :

13.9 Closures

Before we can explore closures, we need to learn about bound variables and free variables.

13.9.1 Bound variables vs. free variables

Per scope, there is a set of variables that are mentioned. Among these variables we distinguish:

• Bound variables are declared within the scope. They are parameters and local variables.
• Free variables are declared externally. They are also called non-local variables .

Consider the following code:

In the body of func() , x and y are bound variables. z is a free variable.

13.9.2 What is a closure?

What is a closure then?

A closure is a function plus a connection to the variables that exist at its “birth place”.

What is the point of keeping this connection? It provides the values for the free variables of the function – for example:

funcFactory returns a closure that is assigned to func . Because func has the connection to the variables at its birth place, it can still access the free variable value when it is called in line A (even though it “escaped” its scope).

Static scoping is supported via closures in JavaScript. Therefore, every function is a closure.

13.9.3 Example: A factory for incrementors

The following function returns incrementors (a name that I just made up). An incrementor is a function that internally stores a number. When it is called, it updates that number by adding the argument to it and returns the new value.

We can see that the function created in line A keeps its internal number in the free variable startValue . This time, we don’t just read from the birth scope, we use it to store data that we change and that persists across function calls.

We can create more storage slots in the birth scope, via local variables:

13.9.4 Use cases for closures

What are closures good for?

For starters, they are simply an implementation of static scoping. As such, they provide context data for callbacks.

They can also be used by functions to store state that persists across function calls. createInc() is an example of that.

And they can provide private data for objects (produced via literals or classes). The details of how that works are explained in Exploring ES6 .

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Declare Multiple Variables in a Single Line in JavaScript

By James L.

The most common way to declare multiple variables in JavaScript is to declare each variable individually on its own line.

For example:

However, there are times when you may want to group related variables together to provide a clear context of their usage. This is where declaring multiple variables on one line can be handy.

In JavaScript, there are several ways to declare multiple variables in a single line.

In this blog post, we will discuss the following methods:

Using comma separator

Using destructuring assignment with arrays and objects.

To declare multiple variables in JavaScript, you can use the var , let or const keyword followed by a comma-separated list of variable names, each initialized with corresponding values

var x = 5, y = 10, z = 15;

let x = 5, y = 10, z = 15;

const x = 5, y = 10, z = 15;

Avoid using var unless you absolutely have to, such as when supporting old browsers. This is because var variables can be redeclared and reassigned anywhere in your code, which can lead to unexpected behavior.

Do keep in mind that variables declared with the const keyword cannot be reassigned later in JavaScript. This means that their value cannot be changed once it has been initialized.

You can also declare multiple variables of different data types in a single line.

If you do not know the value of variables at the time of declaration then you can declare multiple variables using var or let keyword and assign their values later as follows:

However, you cannot use const keyword to declare multiple variables in one line and assign their values later.

This is because each variable created with const keyword must be initialized with a value at the time of declaration.

For example, this is not allowed:

Another way to assign multiple variables in JavaScript is to use the destructuring assignment, which allows you to unpack values from arrays or properties from objects into distinct variables.

Destructuring assignment makes sense when you have an array or object and want to extract its values to variables.

In general, it is best to declare each variable on a separate line, with its own assignment statement. This makes your code more readable and easier to maintain.

However, there are cases where it may be convenient to declare multiple variables on one line, such as when you are grouping related together, or when you are extracting values from an object or array using destructuring assignment.

Use single line multiple variable assignment sparingly.

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multiple assignment javascript

Answered on: Monday 11 December, 2023 / Duration: 15 min read

Programming Language: JavaScript , Popularity : 4/10

Solution 1:

Multiple assignment in JavaScript

In JavaScript, you can assign multiple values to multiple variables in a single statement. This is called *multiple assignment*.

To perform multiple assignment, you use the following syntax:

This code will assign the values 1 , 2 , and 3 to the variables x , y , and z , respectively.

You can also use multiple assignment to swap the values of two variables. For example, the following code will swap the values of the variables a and b :

Multiple assignment can be a very useful shorthand for assigning multiple values to multiple variables. However, it is important to use it carefully, as it can be easy to make mistakes.

Code examples

The following code examples demonstrate how to use multiple assignment in JavaScript:

* Assigning multiple values to multiple variables:

* Swapping the values of two variables:

The following are the outputs of the code examples above:

Solution 2:

In JavaScript, multiple assignment refers to the ability to assign values to multiple variables in a single statement. This feature is particularly useful when you want to assign values from an array, object, or another iterable to multiple variables at once. Here are examples of multiple assignment in JavaScript:

### 1. Array Destructuring:

### 2. Object Destructuring:

### 3. Swapping Values:

### 4. Function Returning Multiple Values:

### 5. Rest Parameter in Array Destructuring:

These examples showcase different scenarios where multiple assignment can be employed in JavaScript, offering concise and readable code.

Solution 3:

In JavaScript, it is possible to assign multiple values to a single variable using the comma operator. This is known as a "multiple assignment" or "tuple assignment."

Here's an example of how you can use multiple assignment in JavaScript:

In this example, we declare three variables x , y , and z and then assign them all the value 10 using the comma operator. When we log each variable to the console, they all output 10 .

It's important to note that when using multiple assignment, the right-most expression is evaluated first, and its result is assigned to the left-hand side variables from right to left. So in the example above, z gets the value 10 first, then y , and finally x .

Multiple assignment can also be used with function returns, like so:

In this example, the function foo() returns an array of three values, which are then assigned to the variables x , y , and z from right to left.

Another way to do multiple assignment is by using destructuring, which allows you to extract values from arrays or objects and assign them to separate variables. Here's an example:

In this example, we define an object obj with two properties, a and b . We then use destructuring to extract those values and assign them to separate variables a and b .

It's worth noting that while multiple assignment is a powerful feature in JavaScript, it can sometimes make code harder to read and understand, especially for other developers who may not be familiar with the syntax. As such, it's generally considered best practice to avoid using multiple assignment in favor of more explicit and readable code.

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How to declare multiple Variables in JavaScript?

In this article, we will see how to declare multiple Variables in JavaScript. The variables can be declared using var , let , and const keywords. Variables are containers that store some value and they can be of any type.

These are the following ways to declare multiple variables:

Table of Content

Declaring Variables Individually

Declaring variables in a single line, using destructuring assignment.

In this case, we will declare each variable using the var, let, or const keywords.

Example: In this example, we are declaring three different variables.

You can declare multiple variables in a single line using the var, let, or const keyword followed by a comma-separated list of variable names.

Example: In this example, we are defining the three variables at once.

You can also use de-structuring assignments to declare multiple variables in one line and assign values to them.

Example: In this example, we are declaring three different variable by destructuring them at once.

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Destructuring assignment

The two most used data structures in JavaScript are Object and Array .

• Objects allow us to create a single entity that stores data items by key.
• Arrays allow us to gather data items into an ordered list.

However, when we pass these to a function, we may not need all of it. The function might only require certain elements or properties.

Destructuring assignment is a special syntax that allows us to “unpack” arrays or objects into a bunch of variables, as sometimes that’s more convenient.

Destructuring also works well with complex functions that have a lot of parameters, default values, and so on. Soon we’ll see that.

Array destructuring

Here’s an example of how an array is destructured into variables:

Now we can work with variables instead of array members.

It looks great when combined with split or other array-returning methods:

As you can see, the syntax is simple. There are several peculiar details though. Let’s see more examples to understand it better.

It’s called “destructuring assignment,” because it “destructurizes” by copying items into variables. However, the array itself is not modified.

It’s just a shorter way to write:

Unwanted elements of the array can also be thrown away via an extra comma:

In the code above, the second element of the array is skipped, the third one is assigned to title , and the rest of the array items are also skipped (as there are no variables for them).

…Actually, we can use it with any iterable, not only arrays:

That works, because internally a destructuring assignment works by iterating over the right value. It’s a kind of syntax sugar for calling for..of over the value to the right of = and assigning the values.

We can use any “assignables” on the left side.

For instance, an object property:

In the previous chapter, we saw the Object.entries(obj) method.

We can use it with destructuring to loop over the keys-and-values of an object:

The similar code for a Map is simpler, as it’s iterable:

There’s a well-known trick for swapping values of two variables using a destructuring assignment:

Here we create a temporary array of two variables and immediately destructure it in swapped order.

We can swap more than two variables this way.

The rest ‘…’

Usually, if the array is longer than the list at the left, the “extra” items are omitted.

For example, here only two items are taken, and the rest is just ignored:

If we’d like also to gather all that follows – we can add one more parameter that gets “the rest” using three dots "..." :

The value of rest is the array of the remaining array elements.

We can use any other variable name in place of rest , just make sure it has three dots before it and goes last in the destructuring assignment.

Default values

If the array is shorter than the list of variables on the left, there will be no errors. Absent values are considered undefined:

If we want a “default” value to replace the missing one, we can provide it using = :

Default values can be more complex expressions or even function calls. They are evaluated only if the value is not provided.

For instance, here we use the prompt function for two defaults:

Please note: the prompt will run only for the missing value ( surname ).

Object destructuring

The destructuring assignment also works with objects.

The basic syntax is:

We should have an existing object on the right side, that we want to split into variables. The left side contains an object-like “pattern” for corresponding properties. In the simplest case, that’s a list of variable names in {...} .

For instance:

Properties options.title , options.width and options.height are assigned to the corresponding variables.

The order does not matter. This works too:

The pattern on the left side may be more complex and specify the mapping between properties and variables.

If we want to assign a property to a variable with another name, for instance, make options.width go into the variable named w , then we can set the variable name using a colon:

The colon shows “what : goes where”. In the example above the property width goes to w , property height goes to h , and title is assigned to the same name.

For potentially missing properties we can set default values using "=" , like this:

Just like with arrays or function parameters, default values can be any expressions or even function calls. They will be evaluated if the value is not provided.

In the code below prompt asks for width , but not for title :

We also can combine both the colon and equality:

If we have a complex object with many properties, we can extract only what we need:

The rest pattern “…”

What if the object has more properties than we have variables? Can we take some and then assign the “rest” somewhere?

We can use the rest pattern, just like we did with arrays. It’s not supported by some older browsers (IE, use Babel to polyfill it), but works in modern ones.

It looks like this:

In the examples above variables were declared right in the assignment: let {…} = {…} . Of course, we could use existing variables too, without let . But there’s a catch.

This won’t work:

The problem is that JavaScript treats {...} in the main code flow (not inside another expression) as a code block. Such code blocks can be used to group statements, like this:

So here JavaScript assumes that we have a code block, that’s why there’s an error. We want destructuring instead.

To show JavaScript that it’s not a code block, we can wrap the expression in parentheses (...) :

Nested destructuring

If an object or an array contains other nested objects and arrays, we can use more complex left-side patterns to extract deeper portions.

In the code below options has another object in the property size and an array in the property items . The pattern on the left side of the assignment has the same structure to extract values from them:

All properties of options object except extra which is absent in the left part, are assigned to corresponding variables:

Finally, we have width , height , item1 , item2 and title from the default value.

Note that there are no variables for size and items , as we take their content instead.

Smart function parameters

There are times when a function has many parameters, most of which are optional. That’s especially true for user interfaces. Imagine a function that creates a menu. It may have a width, a height, a title, an item list and so on.

Here’s a bad way to write such a function:

In real-life, the problem is how to remember the order of arguments. Usually, IDEs try to help us, especially if the code is well-documented, but still… Another problem is how to call a function when most parameters are ok by default.

That’s ugly. And becomes unreadable when we deal with more parameters.

Destructuring comes to the rescue!

We can pass parameters as an object, and the function immediately destructurizes them into variables:

We can also use more complex destructuring with nested objects and colon mappings:

The full syntax is the same as for a destructuring assignment:

Then, for an object of parameters, there will be a variable varName for the property incomingProperty , with defaultValue by default.

Please note that such destructuring assumes that showMenu() does have an argument. If we want all values by default, then we should specify an empty object:

We can fix this by making {} the default value for the whole object of parameters:

In the code above, the whole arguments object is {} by default, so there’s always something to destructurize.

Destructuring assignment allows for instantly mapping an object or array onto many variables.

The full object syntax:

This means that property prop should go into the variable varName and, if no such property exists, then the default value should be used.

Object properties that have no mapping are copied to the rest object.

The full array syntax:

The first item goes to item1 ; the second goes into item2 , and all the rest makes the array rest .

It’s possible to extract data from nested arrays/objects, for that the left side must have the same structure as the right one.

We have an object:

Write the destructuring assignment that reads:

• name property into the variable name .
• years property into the variable age .
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Create the function topSalary(salaries) that returns the name of the top-paid person.

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Doctor linked to multiple deaths after severing a baby’s penis in botched circumcision

The doctor reportedly did not tell the infant’s parents that his medical license had been revoked 10 days prior, article bookmarked.

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A former doctor in Florida has been linked to numerous mishandled medical procedures , including an infant’s botched circumcision and six patient deaths.

Berto Lopez, who spent 33 years working as an OB-GYN - a doctor who cares for pregnant women and women’s reproductive organs - in Palm Beach County , was found liable for $100 million dollars last week after he lost a medical malpractice suit stemming from the botched circumcision.

In 2021, Lopez severed an infant's penis, and did so 10 days after the Florida Board of Medicine voted to revoke his medical license, according to USA TODAY .

The child's family and expert witnesses showed jurors graphic and disturbing images of the aftermath of the circumcision. The family's attorney, Gary Cohen, used the unfortunate phrase "bleeding, scabby mess" to describe what jurors were seeing.

Lopez has been involved in at least 14 serious injuries sustained by women and children in his care, according to The Palm Beach Post , which reviewed court records and other documentation from his time as a physician.

In six cases, people died.

According to the outlet, Lopez has been named in the four disciplinary cases and nine malpractice suits, including two involving the death of infants, an injury to a third infant, and an 18-year-old mom who died during the 1990s.

A typical OB-GYN, on average, faces two to three lawsuits across their career, according to the paper.

Lopez’s license was ultimately revoked after the death of Onystei Castillo-Lopez, a 40-year-old woman who was having her second child while in his care.

Castillo-Lopez suffered tears in her cervix while she was giving birth. She ultimately bled out and died.

Lopez reportedly tried to repair the woman's cervix inside of a hospital suite rather than in an operating room, according to the Florida Department of Health. She died a few months later after Lopez performed the wrong procedure to address her cervical bleeding, according to an administrative complaint.

The state's Board of Medicine had, at that point, already restricted Lopez's license following several other deaths and injuries tied to him months earlier. According to the records reviewed by the Palm Beach Post , Lopez did not inform the mother and her husband that his license had been restricted. He has yet to pay the settlement amount he owes Castillo-Lopez’s husband.

The doctor also did not inform the parents of the baby who was injured in the botched circumcision, according to the family's lawyer.

"If he did, they would have run out that door so fast it would have broken," Cohen said during the trial.

After Lopez cut off a third of the baby's penis, he insisted to his father that the bleeding was normal and spent 45 minutes trying to stop the blood. The next day, the parents took the baby to an emergency room, where they were immediately sent to a pediatric urologist.

The urologist was "visibly shocked" after seeing what had happened to the child, according to the father.

The boy is now three years old, and his parents say he is traumatized by the experience.

"It's never going to heal and no matter what you do, even if you had the money to try to look into something, there’s no restorative surgery that can fix it," the boy's father, Michael Lubben, told WPBF . "He’s not old enough now to realize he’s different, but in just a couple of years, he will be."

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• Dominik Kubalík Signs In Switzerland
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Brad Marchand Underwent Multiple Offseason Surgeries, Expected To Be Ready For Season

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Pro Hockey Rumors

September 3, 2024 at 1:07 pm CDT | by Josh Erickson 6 Comments

Bruins captain  Brad Marchand   underwent a trio of surgeries this summer, he told reporters at an informal skate Tuesday ( via Ty Anderson of 98.5 The Sports Hub ). The winger may be slightly limited to start training camp later this month but expects to be ready for opening night, per Scott McLaughlin of WEEI .

The first procedure Marchand had done was to repair a torn tendon in his elbow that plagued him for the entirety of the 2023-24 campaign, he said. He also underwent abdominal and groin surgeries to repair injuries he sustained late in the regular season.

Those injuries barely cost Marchand any playing time. For the second time in his career, he played in all 82 regular-season games, but he missed two playoff games with what the team called an upper-body injury. That one was presumably addressed with abdominal surgery.

Marchand slowed offensively in 2023-24, but whether that was because of his injuries or age remains to be seen. The 15-year veteran is entering his age-36 season and posted 67 points (0.82 per game) last year, his lowest per-game rate since 2015-16. He still managed to finish second on the team in scoring behind  David Pastrňák and helped lead the Bruins to their first playoff series win since 2021 in his first season as captain following  Patrice Bergeron ’s retirement.

He’ll reprise his top-six role this season, but likely not on a line with Pastrňák with free-agent signing Elias Lindholm   down the middle. Marchand said he expects to start the year back on the team’s second line, centered by Charlie Coyle ( via Conor Ryan of The Boston Globe ).

It’s an important campaign for Marchand as he kicks off the final year of the eight-year, $49MM extension he signed back in 2016. General manager  Don Sweeney said in May that signing Marchand to an extension was one of his top priorities this summer, but it hasn’t happened yet.

19 hours ago

Only in hockey can you need 3 surgeries and play all 82 games lol.

18 hours ago

13 hours ago

What is his rating?

15 mins ago

17 hours ago

the two missed playoff games with ‘upper-body injury’ was due to a concussion.

Immunity disease cuz he licked to many opponents

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Multiplication assignment (*=)

The multiplication assignment ( *= ) operator performs multiplication on the two operands and assigns the result to the left operand.

Description

x *= y is equivalent to x = x * y , except that the expression x is only evaluated once.

Multiplication assignment using numbers

Other non-BigInt values are coerced to numbers:

Multiplication assignment using BigInts

Specifications.

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• Assignment operators in the JS guide
• Multiplication ( * )

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• Mass Legal Employer Change

Change the legal employer of multiple employees in a single batch using the Mass Legal Employer Change task. The application copies the assignment and work relationship data from source to destination work relationship for all the employees as of the global transfer date.

If you update anything after the global transfer date, the application doesn't copy that data.

You can also select employees from different legal employers for transferring to the same destination legal employer. If you select employees from different LDGs, the application copies only the data for those employees transferring within the LDG. However, the global transfer and any override values apply to only those employees that you have selected for the transfer.

What's Copied

Select the data that you want to copy from the source to the target assignment and payroll relationship within the legislative data group.

Payroll relationship and assignment attributes such as Payroll.

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Recurring element entries : The application copies element entries subject to eligibility. To exclude certain elements from being copied, define an element (object) group with the usage type as Global Transfer.

If both the legal employers share the same payroll statutory unit, and if the Tax Reporting Unit attribute is made available in the mass change legal employer flow and you specify a value during the transfer, the application does the following:

After the flow is submitted for all the employees included in the flow, their tax reporting unit association information is updated with the specified tax reporting unit value as of the transfer date on their existing personal deduction card

An association detail record is created for their newly added assignment with effective start date set to the transfer date on their existing personal deduction card

If both the legal employers are associated to different payroll statutory units and the transfer-in legal employer is a newly set up company, the application does the following:

After the flow is submitted for all the employees covered in the flow, a new payroll relationship is created for them on the transfer date

A new personal deduction card with the card details is copied over except association information

If the Tax Reporting Unit attribute is made available in the flow and a value is specified during the transfer, then both the association and association details information is created for them as of the transfer date

After you perform a mass legal employer change, you can view the messages of the copy process on the Change Legal Employer Dashboard.

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Phillies Designate Michael Rucker For Assignment

By Steve Adams | September 4, 2024 at 10:39am CDT

The Phillies announced Wednesday that right-hander Michael Rucker has been designated for assignment. His spot on the 40-man roster will go to fellow righty Nick Nelson , whose contract has been selected from Triple-A Lehigh Valley. Philadelphia also optioned righty Tyler Phillips to Lehigh Valley to open a spot on the active roster for Nelson.

Rucker, 30, was acquired in a cash deal with the Cubs back in February after he’d been designated for assignment in Chicago. He never got into a game with the Phillies in the majors, instead spending most of the season on the 60-day injured list owing to an arterial vasospasm in his right hand. The Phils reinstated and optioned him prior to the trade deadline. He’s pitched 26 minor league innings this season and been tagged for a 6.58 ERA, with the bulk of the damage coming in Triple-A.

Grim as Rucker’s run-prevention has been, his 26.7% strikeout rate and 8.6% walk rate are both fine marks (particularly the former). He’s also kept the ball on the ground at a strong 45.2% clip. Rucker, however, has been plagued by an astronomical .479 average on balls in play during his time with the IronPigs.

As recently as 2022, Rucker was a solid member of the Cubs’ bullpen. He pitched a career-high 54 2/3 innings and logged a 3.95 ERA with a 21.8% strikeout rate and 8.7% walk rate in that time. His followup effort in 2023 resulted in a more troubling 4.91 ERA in 40 2/3 frames, but his strikeout and walk numbers remained generally serviceable and his grounder rate spiked to a strong 51.4%. Overall, Rucker carries a 4.96 ERA in 123 1/3 innings as a major leaguer.

Rucker will now head to waivers, where another club could have interest in his solid Triple-A track record. If not, he’ll be outrighted off the 40-man roster and stick with the Phillies as a depth piece. Rucker lacks the three years of service or prior outright assignment to elect free agency.

The 26-year-old Phillips has had one of the strangest debut campaigns in recent memory. The unheralded righty dominated through his first four big league outings, culminating a shutout of the AL Central-leading Guardians on July 27. He didn’t last two innings in his next start, yielding eight runs to a light-hitting Mariners offense, and has yet to recover. His struggles reached a tipping point when he allowed six runs in the first inning versus the Blue Jays in yesterday’s start. Overalll, since his shutout, Phillips has yielded 23 runs in just 11 2/3 innings. His ERA has skyrocketed from 1.80 to 6.87.

Taking Phillips’ spot on the roster will be Nelson, who’s spent the past three seasons with the Phils. He only pitched in 3 1/3 innings this season and has struggled to produce in Triple-A, where he’s logged a 6.30 ERA on the season. It could be a quick stay on the 40-man roster in Nelson’s return, but he’s stretched out for multiple innings and could give the Phillies four or even five innings of work on the heels of yesterday’s marathon game for the bullpen, if needed. Nelson tossed four innings in a Triple-A appearance as recently as Aug. 24. And, while he’s struggled on the season overall, Nelson has been throwing better of late; he’s yielded only one run in his past 9 1/3 innings pitched in Triple-A.

22 hours ago

I knew he wouldn’t work out. The man has a sword for a hand for goodness sake.

But it was sad that Daryl had to brain his own brother.

21 hours ago

I’m lost – which brother Daryl?

Walking Dead show scene where Daryl had to put Michael Rookers character down cause he turned.

20 hours ago

I believe it was his other brother Daryl. (Newhart (tv show) reference.)

19 hours ago

That is what I was referencing… ; )

I respect him for making the transition to baseball after playing years for the Carolina Panthers. Hopefully he can bounce back

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JS Reference

Html events, html objects, other references, javascript object.assign(), description.

The Object.assign() method copies properties from one or more source objects to a target object.

Related Methods:

Object.assign() copies properties from a source object to a target object.

Object.create() creates an object from an existing object.

Object.fromEntries() creates an object from a list of keys/values.

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Javascript multiple assignment statement

I saw that line in some code

How does it work?

Does the following always return true?

window.a == a

6 Answers 6

OR You can say.

two assignments in a single statment

And one more thing window.a==a right?

yes this is Right. It will return true

• Y u no include iframes or nodejs in your window.a == a statement? –  Petah Commented Dec 3, 2012 at 9:04

This assignment runs from right to left, so at first 'window.b' will be assigned with 'a' value then 'window.a' will be assigned with 'windows.b' value.

You can break this multiple assignment like this and get the same results:

You should be also aware of something like scoping. If you run this code in global scope, eg simple script like this:

window.a==a is true, because 'a' and 'window.a' are the same variables. 'a' is really a property of 'window' object. All global variables are properties of 'window' object. Knowing that you can write you code like this, and this code will be corresponnding:

But if you put this code in a function, it runs in function scope, eg:

And no, window.a and a is not always equal. Typically it is only equal on the global scope in a web browser JavaScript interpreter.

The a and b properties on the window are being assigned to the value of a . Yes, if this code is executed in the global scope, a and window.a are the same.

It's the same like:

window.a == a will be true in this case, after the statements above. There are some cases that it will be false, for example: when a is a global variable.

And one more thing: please find more informative title for your question next time.

Actually, window.a==a can be false if a has the value Number.NaN . That's because Number.NaN is not equal to any value, including itself.

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JSmol Viewer

A backpropagation-based algorithm to optimize trip assignment probability for long-term high-speed railway demand forecasting in korea, featured application, 1. introduction.

• Define a departure node (station or stop);
• Move to and board the vehicle that arrives first at the departure node among the competing routes;
• Get off at the intermediate node (station or stop) that was determined according to the optimal strategy;
• End if the passenger arrives at their destination; otherwise, define the alighting node as the departure node and repeat from step 1.

2. Standard Long-Term HSR Demand-Forecasting Methodology in Korea

3.1. trip assignment probability, 3.2. optimization algorithm, 4. case study, 4.1. data description.

• i : zone ( ∀ i   ∈   Z );
• s : HSR station ( ∀ s   ∈ S);
• d i s : Euclidean distance from zone i to station s ;
• x , y : x -coordinate and y -coordinate.
• Z: The set of zones;
• S: The set of HSR stations.

4.2. Results

• i : HSR station ( ∀ i   ∈   Z );
• n : the number of HSR stations;
• f e s t : the estimated number of passengers at each station using the trip assignment model;
• f o b s : the observed number of passengers at each station.

5. Conclusions

Institutional review board statement, informed consent statement, data availability statement, conflicts of interest.

Click here to enlarge figure

• Line 105: “opt_target_tensor” is the tip assignment probability weight tensor for all stations ( T a ) in Figure 5 .
• Line 106: “prob_mask_tensor” is the accessible station tensor ( T b ) in Figure 5 .
• Line 119: “z_masked” is the trip assignment probability weight tensor ( T c ) in Figure 5 .
• Line 126–128: A normalization process in Figure 6 .
• Line 130: “t_1” is the assigned trip tensor ( T g ) in Figure 7 .
• Line 131: “t_2” is the assigned sum trip tensor ( T h ) in Figure 8 .
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Share and Cite

Kwak, H.-C. A Backpropagation-Based Algorithm to Optimize Trip Assignment Probability for Long-Term High-Speed Railway Demand Forecasting in Korea. Appl. Sci. 2024 , 14 , 7880. https://doi.org/10.3390/app14177880

Kwak H-C. A Backpropagation-Based Algorithm to Optimize Trip Assignment Probability for Long-Term High-Speed Railway Demand Forecasting in Korea. Applied Sciences . 2024; 14(17):7880. https://doi.org/10.3390/app14177880

Kwak, Ho-Chan. 2024. "A Backpropagation-Based Algorithm to Optimize Trip Assignment Probability for Long-Term High-Speed Railway Demand Forecasting in Korea" Applied Sciences 14, no. 17: 7880. https://doi.org/10.3390/app14177880

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Police Interviewed Georgia Suspect About Shooting Threats in 2023

The 14-year-old student accused of killing four people with a military-style rifle at his Georgia high school was questioned about online threats last year, the F.B.I. said.

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Shooting at Georgia High School Leaves Four Dead

The police responded to a shooting at apalachee high school in winder, ga. at least nine others were injured..

“Hurry up now. Come on, let’s go.” “What the —” “We got a whole school to get evacuated, people. Come on, now. Come on. Far left. Far left. Let’s move with purpose. Come on.” “Yeah, really sad.” “It took us a while before we realized that she wasn’t one of the victims. I mean, that’s what, a good 45 minutes?” “Hour.” “An hour before we got word that she was OK. It was very terrifying. It’s the least thing you’d expect to happen.” “I don’t know how to explain the feelings. I mean, the fear — I have two children that go to Haymon-Morris, which is, borders this school. And so first thing was immediately calling the schools. Then the text messages and stuff started coming through from the schools. Terror — absolute terror.”

Follow the latest updates on the shooting .

Rick Rojas and Alessandro Marazzi Sassoon

Reporting from Georgia

Nine people were expected to survive their injuries. Here’s what else to know.

A 14-year-old student accused of killing four people at his Georgia high school had been interviewed by law enforcement officers last year in connection with threats of a school shooting posted online, officials said.

Barely a month into the new school year, the student opened fire with a military-style rifle on Wednesday at Apalachee High in Winder, Ga., killing two students and two teachers. He surrendered when confronted by school resource officers, according to the authorities, who said the suspect would be charged with murder.

Students described their terror as a lockdown that they initially thought was a drill yet turned out to be anything but. They said they heard gunfire and barricaded themselves in classrooms, then later fled to the football field to reunite with anxious parents.

The attack, which also injured eight students and a teacher, stoked fear and anguish in Winder, a city of roughly 18,000 people in the exurbs of Atlanta, as the community grappled with a burst of violence that the local sheriff described as “pure evil.”

Here’s the latest:

Officials identified the 14-year-old suspect as Colt Gray, and said that he would be prosecuted as an adult. Chris Hosey, the director of the Georgia Bureau of Investigation, said the shooter had used an “AR-platform-style weapon.” The authorities were still investigating how he had gained access to the gun. Rifles based on the AR-15 design have been commonly used in mass shootings.

All of the victims who were at the hospital were expected to survive their injuries, Mr. Hosey said.

The suspect had been on the radar of law enforcement officials for more than a year, in connection with threats of a school shooting posted online, the F.B.I. said . When interviewed by local law enforcement officials, he denied making the threats, and his father said that his son did not have unsupervised access to weapons.

The shooting was the deadliest episode of school violence in Georgia history , and prompted an outpouring of sympathy and outrage. President Biden, in a statement, lamented the attack as “another horrific reminder of how gun violence continues to tear our communities apart.”

Jacey Fortin contributed reporting.

Christina Morales

What we know about the Apalachee High School shooting victims.

The shooting at Apalachee High School in Winder, Ga., on Wednesday killed two teachers and two students, becoming the deadliest episode of school violence in the state’s history. At least nine others were injured.

The authorities identified the dead students as two 14-year-olds, Mason Schermerhorn and Christian Angulo. The educators killed were identified as Richard Aspinwall and Christina Irimie, officials said. Spellings of the names were not confirmed by the authorities.

Law enforcement officials said in a news conference that the victims taken to the hospital were expected to make a full recovery.

“Those that are deceased are heroes in my book,” said Chris Hosey, director of the Georgia Bureau of Investigation. “Those that are in the hospital recovering right now are heroes in my book.”

Mason Schermerhorn was described by friends of his family as a lighthearted teenager who liked spending time with his family, reading, telling jokes, playing video games and visiting Walt Disney World. He had recently started at the school.

“He really enjoyed life,” said Doug Kilburn, 40, a friend who has known Schermerhorn’s mother for a decade. “He always had an upbeat attitude about everything.”

Louis Briscoe, a co-worker and friend of Schermerhorn’s mother, said the boy and his family were looking forward to an upcoming vacation there.

When Mr. Briscoe learned about the shooting at the high school in the afternoon, he called Schermerhorn’s mother to ask if everything was OK. She told him: “Mason’s gone.”

“My heart just dropped,” said Mr. Briscoe, 45. He added, “Nobody should have to go through this type of pain.”

The gunman — who the authorities identified as a 14-year-old student at the school — will be charged with murder, officials said. Students heard gunfire as they barricaded themselves in classrooms.

The shooting has shaken residents in Winder, which has about 18,000 residents and is roughly 50 miles northeast of downtown Atlanta.

At the high school, Ms. Irimie and Mr. Aspinwall were math teachers. Mr. Aspinwall was also the football team’s defensive coordinator.

David Phenix, a math special education teacher and the school’s golf coach, was injured during the shooting. Katie Phenix, his daughter, said in a Facebook post on Wednesday that he was shot in the foot and hip, shattering his hip bone.

“He arrived to the hospital alert and awake,” she wrote in the post, adding that he had surgery earlier that day.

Kate Selig and Rachel Nostrant contributed reporting.

The suspect was interviewed about online threats of a school attack last year.

Federal investigators said on Wednesday that the suspect in the shooting at a Georgia high school had been interviewed more than a year ago by local law enforcement officials in connection to threats made online of a school shooting.

The authorities were led to the suspect, Colt Gray, who was 13 at the time, after the F.B.I.’s National Threat Operations Center received several anonymous tips in May 2023 reporting threats that had been posted on an online gaming site warning of a school shooting at “an unidentified location and time,” according to statements from the F.B.I. field office in Atlanta and local law enforcement officials. The threats included photographs of guns.

Investigators from the sheriff’s office in Jackson County, Ga., interviewed the suspect and his father, the F.B.I. said. His father told investigators that he had hunting guns in the house, but said that his son did not have unsupervised access to the weapons. The suspect denied making the threats.

The F.B.I. said that the Jackson County authorities alerted local schools “for continued monitoring of the subject.” But it was unclear if officials at Apalachee High School, where the shooting took place and the suspect was a student this year, had been among those informed; the school is in Winder, Ga., in neighboring Barrow County.

The F.B.I., in its statement, said that investigators lacked probable cause to arrest the teenager or “take any additional law enforcement action on the local, state or federal levels.”

In a separate statement, Janis G. Mangum, the sheriff in Jackson County, said that a “thorough investigation was conducted,” but that “the gaming site threats could not be substantiated.”

Ms. Mangum cautioned residents to be careful of posts containing misinformation circulating online. “My phone is blowing up with messages from people about social media postings about other possible incidents,” she said in a note on Facebook. “To my knowledge, there is not a list indicating any of this.”

Alexandra E. Petri

All of the victims who were at the hospital were expected to survive their injuries, the authorities said.

Alessandro Marazzi Sassoon

About 400 people gathered at a candlelight vigil just before sunset in Winder's Jug Tavern Park. Two local officials spoke briefly, followed by a sermon from Geoffrey Murphy, the senior pastor of Winder First United Methodist Church, and a moment of silence.

The weapon used in the shooting was an “AR-platform-style weapon,” said Chris Hosey, director of the Georgia Bureau of Investigation, at a news conference.

The authorities are still investigating how the suspect gained access to the gun, Hosey said.

The AR-15-style semiautomatic rifle has been commonly used by mass shooters in the past, and is one of the most ubiquitous weapons in the United States.

Some quick thinking by one student ‘saved us,’ a classmate says.

Bryan Garcia heard what sounded like gunfire — boom, boom, boom, he said — coming from outside his math class at Apalachee High School. A lockdown alert flashed on a screen inside the room.

Following protocol, the students and teacher ran to the back of the class and huddled in the corner furthest from the door.

Bryan looked toward the door. It was open.

Almost immediately, Bryan said, a classmate ran across the room and slammed the door shut.

“He saved us,” Bryan said.

Another student, Nahomi Licona, described a similar scene in her math class. As students hustled to the back of the room, she said, one of them ran up to close the door. They heard gunshots, then footsteps, then lots of shouting, she said.

Nahomi, 15, a sophomore, said her family moved to the United States nine years ago from Guatemala. Walking beside Nahomi on Wednesday afternoon, her mother, Jackeline, said shootings in their native country tended to happen in the streets, not in schools. Nahomi said she recognized the sound of gunfire at once.

“It’s normal over there, but it’s still scary,” Nahomi said. She added: “I never expected to hear that in a school.”

Within a few minutes, Bryan said, school resource officers responded. Bryan said he heard a confrontation involving the shooter, whom the authorities identified as a 14-year-old student at the school. The officers were engaging the suspect, Bryan said, telling him to raise his hands and surrender.

Nahomi said she knew people were at least injured while she was evacuating the school. In a hallway, she said, she saw white powder used to absorb blood.

The suspect had been on the radar of law enforcement officials more than a year ago in connection with threats of a school shooting posted online, the F.B.I. said. He and his father were interviewed by local law enforcement officials; he denied making the threats, but the authorities alerted local schools.

In an interview on CNN, Lyela Sayarath, a junior at Apalachee High School who said she sat next to the shooter, described him as a “quiet kid” who recently transferred into the school and often skipped class. “He never really spoke,” she said. “I couldn’t tell you what his voice sounded like, or really even describe his face to you. He was just there.”

Richard Fausset

A mother and daughter endured lockdowns in separate schools before they could reunite.

Anetra Pattman, 43, was teaching social sciences at the alternative school in Barrow County, Ga., when she received a text on Wednesday at 10:24 a.m.

It was from her 14-year-old daughter, Macey Wright, at Apalachee High. It said, “Mom, I heard gunshots. I’m scared. Please come get me.”

Dr. Pattman knew that she could not hurry to her daughter. She had to stay with her own students, and keep calm.

“At that moment, the primary thing was continuing this communication with my daughter, but now I’m also responsible for keeping my other children safe,” she said of her students.

Then her own school went into hard lockdown mode. Her students hid in the corner. Lights out. Quiet. They stayed that way from 11 a.m. to about 1:30 p.m.

The reunion of mother and daughter finally came about an hour later. A friend had picked Macey up from Apalachee and taken her to a convenience store, where her mother was waiting. They hugged each other and cried.

Two students and two teachers were killed at Apalachee, the authorities said, and at least nine other people were injured.

Macey’s friend, a fellow freshman, had been shot in the shoulder, and Macey was worried about her. She told her mother she did not want to go back to school and get shot.

It was difficult for Dr. Pattman, an educator for 22 years, to accept that so many students have to live with such a possibility every day that they set foot on an American high school campus. But she said that she and her daughter would find a way to soldier on. She spoke on Wednesday afternoon with a resolve that seemed laced with resignation.

“I think most of it just comes from not living in fear, knowing that things like this happen,” she said. “Not just in schools, but in grocery stores, in churches. I’m almost to the point where I feel that no place is exempt.”

Winder, a rural, middle-class city in Georgia, is in a rapidly developing area.

The shooting at Apalachee High School on Wednesday took place in a rural, unincorporated area between the cities of Atlanta and Athens in Georgia.

The school — where a 14-year-old student fatally shot four people and injured nine others, according to the authorities — is on the edge of Winder, which is home to about 20,000 people. The city is roughly 50 miles northeast of downtown Atlanta and about 25 miles west of Athens.

The area around the school , once largely farmland nestled in the Georgia pines, has been developing rapidly in the last 15 years, as new buildings have cropped up along its winding, two-lane roads, according to Winder’s mayor, Jimmy Terrell.

Winder is the seat of Barrow County, which has nearly doubled in population to 83,500 since 2000, according to census data.

Winder is a family-oriented, middle-income community with an aging population, Mr. Terrell said. The area has not had a crime of “this magnitude” since a series of murders in the 1960s and ’70s, Mr. Terrell said in a phone interview.

In Winder, about 60 percent of the population is white, about 20 percent is Black and about 15 percent is Latino, according to census figures. The area has grown more diverse in recent years, Mr. Terrell said. The city’s median household income is about $57,000, according to the census , and about one in five people in the city have attained a bachelor’s degree. Barrow County as a whole has a larger share of families with children than other places in Georgia and the United States, according to the data.

The city leans Republican, Mr. Terrell said. In the 2020 presidential election , Donald J. Trump won Barrow County, which surrounds the city, with about 71 percent of the vote.

Apalachee High School opened in 2000, and has about 1,800 students in grades nine through 12.

Robert Gebeloff and Emmett Lindner contributed reporting.

Alessandro Marazzi Sassoon Richard Fausset and Rick Rojas

Alessandro Marazzi Sassoon and Richard Fausset reported from Winder, Ga., and Rick Rojas from Atlanta.

Students and teachers huddled in fear as the gunfire rang out.

The lockdown alert flashed on a screen in Stephen Kreyenbuhl’s classroom at Apalachee High School as the gunfire started.

Mr. Kreyenbuhl, a world history teacher, said he heard at least 10 shots on Wednesday morning, as the deadliest episode of school violence in Georgia history unfolded around the corner from his room.

Within minutes, four people — two students and two teachers — had been killed on the campus of Apalachee High School, in Winder, roughly 50 miles from downtown Atlanta. The authorities identified the shooter as a 14-year-old student at the school.

Laniel Arteta, a freshman, said he and other students huddled in the corner of their technology classroom, their hands over their heads, after the gunfire erupted. He heard screams, and the voice of his teacher urging the students to stay quiet. They waited like that, he said, for more than an hour.

When Laniel was finally shepherded out of the building with his classmates, he saw scads of police officers. He also saw loose shoes everywhere, but he did not know why, he said. Mr. Kreyenbuhl, 26, said he walked past a “pool of blood.”

Greg Mann, a parent at Apalachee High School, told 11 Alive, the NBC affiliate in Atlanta, that many students, who fled to the football field, had left their phones and keys inside the school. Mr. Mann said he was at the school helping to connect them with their families.

As parents scrambled to reunite with their children, traffic snarled around the school. Shelbey Diamond-Alexander, the chair of the Barrow County Democratic Party, said she was handing out bottles of water to some parents who left their cars to walk the final mile and a half to the school. “It’s a mess out here,” she said. “People are just trying to get their children. It’s devastating for our community.”

Laniel was able to find his father, Harvy Arteta, and at 4 p.m., about a mile from campus, the pair were by the side of a road choked with cars. Helicopters whirred above them. Laniel and his father seemed in shock.

Speaking in Spanish, Laniel said that about two years ago he came to the United States from Nicaragua, a country that has experienced bouts of intense political violence. But Laniel was aware that here, in the United States, there was a particular kind of problem to fear in school.

Now, he said, it was going to be difficult to go back to class.

Mr. Arteta, 40, seemed just as scared to send his son to Apalachee High in the coming days. Because what was to stop it from happening again? “It’s really complicated, going back,” he said.

Adeel Hassan

There have been three mass shootings in the U.S. this year.

The shooting at a high school in Winder, Ga., in which a gunman killed two teachers and two students, and wounded nine more people was the third mass shooting in the United States this year. It is also the deadliest school shooting in Georgia’s history.

The most recent mass shooting happened in Chicago over Labor Day weekend. Four people were killed in each of the two earlier attacks.

By The New York Times’s count, a mass shooting has occurred when four or more people — not including the shooter — have been killed by gunfire in a public place, and no other crime is involved. Our count of mass shootings is based on data from both the Gun Violence Archive and the Violence Project. We use data from both sources in order to make sure our database is as current and comprehensive as possible.

Mass shootings since 1999

Incidents where four or more people were killed in a public place and not connected to another crime.

Here are the other mass shootings that have occurred in the United States this year:

Fordyce, Ark. : A gunman killed four people and wounded nine on June 21 at the Mad Butcher grocery store in a town of 3,400 people, about 70 miles south of Little Rock. Two police officers were injured in the attack, and the shooter was also wounded.

Forest Park, Ill. : A man fatally shot four passengers on Monday as they slept on an L train in the Chicago suburb, according to the authorities.

Wednesday’s school shooting was the deadliest in Georgia’s history.

There have been about 70 shootings at K-12 schools in Georgia between 1970 and June 2022, according to data compiled by the Center for Homeland Defense and Security. But none were as deadly as Wednesday’s attack.

The data is expansive and includes instances where a gun is brandished or fired on school property, or a bullet strikes a school, regardless of the number of victims or the time that the shooting takes place.

Among those, one of the most high-profile school shootings in state history took place in May 1999, one month after the deadly massacre at Columbine High School in Colorado. Then, at Heritage High School in Conyers, about a half-hour southeast of downtown Atlanta, a 15-year-old student opened fire in an indoor common area and injured six students. No deaths were reported.

More recently, in 2019, 10 elementary school students were shot and suffered non-life-threatening injuries at a playground outside Wynbrooke Elementary Theme School in Stone Mountain, about 20 miles northeast of Atlanta.

Before Wednesday, there were four other shootings at Georgia schools this year that resulted in casualties.

In early February, two people were shot and injured in the parking lot of McEachern High School in Powder Springs. Days later, a 15-year-old boy was shot and killed after a basketball game at Tri-Cities High School in East Point.

Then, on Valentine’s Day, four students at Benjamin E. Mays High School in Atlanta were injured after being shot in school’s parking lot.

And in May, a 21-year-old woman was fatally shot on Kennesaw State University’s campus in front of a residential complex. Her former boyfriend was charged with murder in the shooting.

Schools in Barrow County, Ga., will be closed for the rest of the week, said Dallas LeDuff, the superintendent of the county’s school system.

The suspect surrendered when he was confronted by law enforcement, Sheriff Smith said. “He gave up and got on the ground,” the sheriff said, and was then arrested.

In emotional remarks, Sheriff Jud Smith of Barrow County said he “never imagined” he would be in a situation like this one, which he described as “pure evil.” “My heart hurts for these kids,” he said at a news conference.

Sean Plambeck

The suspect, who is in custody, will be charged with murder as an adult, said Chris Hosey, the director of the Georgia Bureau of Investigation.

Stephen Kreyenbuhl, a world history teacher, said he heard at least 10 shots ring out nearby at about the same time that a lockdown alert flashed on a screen in his classroom at the high school. Kreyenbuhl, 26, said teachers and employees all have a key card that can initiate a lockdown if they spot a potential threat.

The authorities identified the shooter as a 14-year-old student at the school. They said the deceased included two students and two teachers.

Former President Donald J. Trump offered his condolences on social media. “Our hearts are with the victims and loved ones of those affected by the tragic event in Winder, Ga.,” he wrote on social media. “These cherished children were taken from us far too soon by a sick and deranged monster.”

Senator Raphael Warnock of Georgia expressed his sadness over the shooting and offered his prayers to the families of victims and the community. “But we can’t pray only with our lips,” Warnock, a Democrat, said in a statement. “We must pray by taking action.”

Emmett Lindner

Layne Saliba, a spokesman for the Northeast Georgia Health System, said the system’s campuses had received eight patients from Apalachee, three gunshot victims and five other patients suffering from anxiety-related symptoms.

Greg Mann, a parent at Apalachee High School, told 11 Alive, the NBC affiliate in Atlanta, that many students, who fled to the football field, had left their phones and keys inside the school and were still trying to get in touch with their families. Mann said he was at the school helping to connect them. “Nobody’s seen this coming,” he said. “You don’t really know what to do.”

Reid J. Epstein

Vice President Kamala Harris, speaking at a campaign rally in New Hampshire, called the Georgia school shooting “outrageous.” “Our kids are sitting in a classroom where they should be fulfilling their God-given potential, and some part of their big beautiful brain is concerned about a shooter busting through the door of their classroom,” she said. “It doesn't have to be this way.”

So before I begin, I do want to say a few words about this tragic shooting that took place this morning in Winder, Ga. We’re still gathering information about what happened, but we know that there were multiple fatalities and injuries. And our hearts are with all the students, the teachers and their families, of course. And we are grateful to the first responders and the law enforcement that were on the scene. But this is just a senseless tragedy on top of so many senseless tragedies. And it’s just outrageous that every day in our country, in the United States of America, that parents have to send their children to school worried about whether or not their child will come home alive. It’s senseless. It is — we got to stop it. And we have to end this epidemic of gun violence in our country once and for all. It doesn’t have to be this way. It doesn’t have to be this way.

The shooting in Georgia on Wednesday was the deadliest at a school this year, based on data from both the Gun Violence Archive and the Violence Project that was reviewed by The New York Times. It is also the deadliest school shooting in state history, according to data from the Gun Violence Archive .

Traffic was snarled around the school as parents scrambled to reunite with their children. Shelbey Diamond-Alexander, the chair of the Barrow County Democratic Party, said she was handing out bottles of water to some parents who left their cars to walk the final mile and a half to the school. “It’s a mess out here,” she said. “People are just trying to get their children. It’s devastating for our community.”

Alessandro Marazzi Sassoon and Rick Rojas

Alessandro Marazzi Sassoon reported from Winder, Ga., and Rick Rojas from Atlanta.

At first, students thought a lockdown was a drill. Then, they heard gunshots.

Students at Apalachee High School had gone through drills to prepare them for how to respond to a shooting on campus. On Wednesday morning, when a lockdown warning flashed in his Spanish classroom, Jose Inciarte assumed that school officials were conducting a test.

“But then we heard keys and running and screaming,” he recalled a few hours later as he left campus.

Jose, 16, and his classmates at Apalachee are part of a generation of students who have learned protocols and tactics for protecting themselves from a gunman as a regular part of their education. Still, students said on Wednesday that there was no way to anticipate the fear they felt as a shooting was actually unfolding at their school, about 50 miles from downtown Atlanta.

Isabella Albes Cardenas, an 11th grader, said she heard doors slamming shut and then what sounded like several gunshots.

“They prepare you for these things,” said Isabella, 15. “But in the moment, I started crying. I got nervous.”

Christian Scott, also in 11th grade, said he had left class and was heading to the nurse’s station. “Suddenly,” he said, “I was under lockdown.”

He could hear the gunshots, he said, “before I blocked it out.” Beds were used to barricade the doors inside the nurse’s office. He called his mother, crying.

Those moments were “living hell,” said Christian, 16.

Eventually, he made it out of the school to the football field, where he reunited with his sister, who is also a student, and his friends.

Susanna Timmons

Because law enforcement officials control crime scenes, we initially rely on the information they provide. We are working aggressively to verify it through interviews with witnesses and victims, and we will report any discrepancies between what officials are saying and what we find. Here’s how we report on mass shootings .

A 14-year-old student at Apalachee High School told Atlanta News First, a local news outlet, that he was sitting by the door in his classroom when “something told me to look to my left.” That’s when he saw the shooter “with a big gun” out of the corner of his eye, he said. The student said he ran to the back of the classroom and hid. He estimated the shooter, who he identified as a man, shot about 10 times, making his ears ring.

The Georgia Bureau of Investigation confirmed that four people had died, but dispelled rumors that the suspect had been “neutralized,” adding that reports of additional shootings at nearby schools were false.

In a statement mourning the victims of the shooting, President Biden called on Republicans to work with Democrats to pass new gun control legislation. “What should have been a joyous back-to-school season in Winder, Georgia, has now turned into another horrific reminder of how gun violence continues to tear our communities apart,” the president said.

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