Functions - Reading Assignment

Javascript Programming
#1009
  1. A function is created with an expression that starts with the keyword function.
  2. let allows you to declare variables that are limited in scope to the block, statement, or expression on which it is used, var keyword defines a variable globally, or locally to an entire function regardless of block scope.
  3. A pure function is a specific kind of value-producing function that not only
    has no side effects but also doesn’t rely on side effects from other code—for
    example, it doesn’t read global bindings whose value might change.
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#1010

**How can you create a function in JavaScript?
You create an expression that starts with the word function, then set the parameters (or not, just parentheses) and add the body (the code that contains the statements to be executed when the function is called, it must be wrapped in braces).

**What is the difference between var and let in regards to scope?
var is global while let has a local biding. In other words, var is “seen” by the whole program. let are bindings that work only in the block that they are declared in. As an example, if we create a let binding inside a loop, the code before and after the loop cannot “see it”.

  1. What is a pure function?
    “A pure function is a value-producing function that has no side effects and it doesn’t rely on side effects from other code, it doesn’t read global variables that are occasionally
    changed by other code. When called with the same arguments, it always produces the same
    value (and doesn’t do anything else).”
    A pure function is a function which:
  • Given the same input, will always return the same output.
  • Produces no side effects.
    Pure functions are completely independent of outside state, and as such, they are immune to entire classes of bugs that have to do with shared mutable state.
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#1011
  1. How can you create a function in Javascript?

Define a constant (whatever word makes sense to describe the function) as a function such as
Const square = function(x) {

Return x * x;

}

  1. What is the difference between var and let in regards to scope?

Var is a Global binding so it will be seen throughout numerous functions. Whereas, let is a local binding so it will only be seen within its own local area.

  1. What is a pure function?

A function that, when called with the same arguments, ALWAYS returns the same value and nothing else. They are helpful because they can be used anytime later in the code and they will behave in the same (and expected) way.

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#1012
  1. A function in Javascript is created as an expression which starts with the keyword “function”. It has a set of parameters and a body, wrapped in braces, that contains the statements to be executed when the function is called.
  2. ‘let’ defines a binding that is only a local binding, ie it can only be referenced within the block or function within which it is defined. On the other hand, “var” defines a binding which is global, ie it can be referenced throughout the whole program, or within a function within which it is defined but outside of the block.
  3. A pure function is a value -producing function which has no side effects and always produces the same value (when called with the same arguments). It does not rely on side effects from other code.
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#1013

  1. A function is created with the expression that starts with the keyword: function. They have a set of parameters and a body, which contains the statements that are to be executed when the function is called.

  2. let keywords are only visible locally meaning after the loop has been closed it is no longer visible. Var keyword however is visible through the whole function, even if inside a local function body.

  3. A pure function - given the same input, will always return the same output, it produces no side effects and does not rely on side effects from other code. It can be reused through a program.

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#1014

  1. creating a function is the process wrapping a value within a program. the primary application is to define that value with a keyword/instruction that can recalled later. the purpose of wrapping this value in a function for recall later when developing larger, more complex programs. simply, you can recall the function with these word identifiers to simplify the integration with larger constructs.

  2. with regard to scope, ‘var’ is a keyword that maintains visibility on a global level, meaning it is visible outside of the binding it is declared, and can be recalled anywhere within the greater function. ‘let’ is restricted to the local level, meaning it is only visible within the binding it is declared and is not visible or available for recall anywhere else in the function (outside of the binding origin).

  3. a pure function is a ‘value’ producing function that has no side effects, and doesn’t reply on side effects from other code. it’s stand alone, doesn’t read global bindings, and always produces the same value.

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#1015
  1. How can you create a function in Javascript? With an expression that starts with a word “function”
    2.What is the difference between var and let in regards to scope? Var is visible throughout the whole scope, let is local to the block that they are declared in
  2. What is a pure function? is a function that will always return the same output, when called with the same argument , has no side effects.
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#1016
  1. How can you create a function in Javascript?
    By using function keyword. function Name(parameter) {code}
  2. What is the difference between var and let in regards to scope?
    Var is global variable, visible to whole function. Let is local variable, visible to the block used in.
  3. What is a pure function?
    Function thats producing value only and has no side effects. Also doesnt rely on side effects from other codes.
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#1017

  1. How can you create a function in Javascript?
    A function is created with an expression that starts with the keyword function. Functions have a set of parameters and a body, which contains the statements that are to be executed when the function is called and must always be wrapped in braces.

  2. What is the difference between var and let in regards to scope?
    In regards to scope, var defines a variable locally, as well as globally; while let declares a variable only locally.

  3. What is a pure function?
    A pure function is a specific kind of value- producing function that not only has no side effects but also doesn´t rely on side effects from other code. It has the property that, when called with the same arguments, it always produces the same value (and doesn´t do anything else).

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#1018
  1. How can you create a function in Javascript?
  2. What is the difference between var and let in regards to scope?
  3. What is a pure function?

1.You need to announce it.
const square = function(x) { return x * x; }
2.let can be more strict in terms of the scope of the varibles. var announcement is usually global. varibles in a function is usually local varibles, but when you use var it can be confusing because it can be recognized as a global varible.
3.pure function is a function that given the same iput will always return the same output with no side effect.

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#1019
  1. How can you create a function in Javascript? By using a keyword function and giving it a parameter and a body.
  2. What is the difference between var and let in regards to scope? a var applies a global scope to a block while a let applies a local scope to a block
  3. What is a pure function? a function that stands on it’s on and produces no side effects.
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#1020

How can you create a function in Javascript?

A lot of the values provided in the default environment have the type function.

A function is a piece of program wrapped in a value. Such values can be applied

in order to run the wrapped program.

function name(parameter1, parameter2, parameter3) {code to be executed}

What is the difference between var and let in regards to scope?

The main difference between let and var is that scope of a variable defined with let is limited to the block in which it is declared while variable declared with var has the global scope

What is a pure function?

A pure function is a function that given the same input will always return the same output and it producess no side effects.

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#1021
  1. You can declare a function by giving it a binding, with curly brackets following it, using the keyword ‘function’ and then declaring the code of the function inside proceeding curly brackets. A function may or may not have parameters.
    i.e. function square(x) { return x * x; }
  2. let declares a variable that’s limited to the block, statement, or expression on which it is used. var defines a variable globally, or locally to an entire function, regardless of block.
  3. A pure function is a special kind of value-producing function that both has no side effects, and isn’t dependent on the side effects of other code either. When called with the same arguments, a pure function will always return the same value.
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#1022

  1. There are 3 different ways to create a function in javascript:

    a) // Defining a binding to hold a function value
    const bindingName = function (parameters) {
    // statement of the function
    };

    b) // Declaring a binding to be a function:
    function bindingName (parameters) {
    // statement of the function
    }

    c) // Arrow function style:
    let bindingName = (parameters) => {
    // statement of the function
    }

  2. When declaring a binding with let in a nested scope (blocks and functions), the scope that
    is wrapped around it can’t see that binding. It is visibile only in the nested scope.

    When declaring a binding with var in a nested scope (blocks, but not functions), the scope that
    is wrapped around it can see that binding.
    However, if the binding is created inside a function, the wrapping scope will not see it.

  3. A pure function is a function that follows this rules:
    a) a pure function does not produce side effects;
    b) a pure function is not influenced by preexisting side effects (such as global binding values)
    already present in the program when it is called.

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#1023

  1. A Function is an expression ( with none or multiple parameter) tied to a binding name.

  2. var is function-scoped and let is block-scoped. However, var outside of a function is globally-scoped.

  3. A pure-function always behaves the same. It doesn’t rely on input or variables outside of its own scope. It will always return the same result.

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#1024
  1. A function is created with an expression that starts with the keyword function.
  2. From what I understand from eloquent js is that when it comes to let and var, “let” is a local binding and “var” is a global binding. In terms of scope, when using the function “let” you will not see it when creating loops where as “var” is visible through out the “global” scope.
  3. A pure function is a specific kind of value-producing function that not only has no side effects but also doesn’t rely on side effects from other code.
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#1025

  1. A function is created with the keyword function and and with the use of a set of parameters using the () and {} to begin and close off the function.

  2. Let is local to the block it’s are declared in, so it can only be used within that block. Var is global, so it can be used throughout the whole function it is declared in.

  3. A pure function gives the same results given the same parameters.

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#1026
  1. created by writing “function” with parameters and a statement that is to be executed.
  2. ‘let’ is limited to the parameters of the function that it is defined in. ‘var’ can be applied/seen throughout the entire block of code.
  3. its a functions that impervious to outside side effects nor produces any side effects. It consistently operates as it should no matter the circumstances.
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#1027
  1. How can you create a function in JavaScript?
  • A function is created with an expression that starts with the keyword function.
  1. What is the difference between var and let in regards to scope?
  • var keyword, is a global binding which are visible throughout the whole function that they appear in, Let is a local binding which is limited to the block so if you create one of those inside of a loop, the code before and after the loop cannot “see” it
  1. What is a pure function?
  • Is a specific kind of value-producing function that not only has no side effects but also doesn’t rely on side effects from other code
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#1028
  1. How can you create a function in Javascript? — function(parameters) { do code } ;
  2. What is the difference between var and let in regards to scope? — Let and const are local to the block they are declared in. Var is global
  3. What is a pure function? — value producing function that has no side effects but also doesn’t rely on other side effects from other code or things that may change like global variables, so only depends on parameters it is passed and given same inputs will always output the same output
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