Functions - Reading Assignment

Javascript Programming
#1189

  1. How can you create a function in Javascript?
    By starting with the keyword “function” which has a set of PARAMETERS and a BODY that contains statements to be executed when that function is called.

  2. What is the difference between var and let in regards to scope?
    let is local to the block that it is declared in, while var is visible throughout the whole function that it appears in - or throughout the global scope if not in a function.

  3. What is a pure function?
    it 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. When a pure function is called with same arguments, it always produces the same value.

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#1190
  1. How can you create a function in Javascript?
    const example = function() {execution code};
  2. What is the difference between var and let in regards to scope?
    “var” can be visible outside of the block it was created in. “let” is only visible in the local environment it’s called in unless it’s created globally.
  3. What is a pure function?
    Pure functions produce values while not relying on side effects from other code
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#1191

  1. Functions can be made with an expression using the keyword function and then giving it a set of parameters.

  2. Var is function scoped and let is block scoped.

  3. A pure function is a function that produces no side effects.

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#1192
  1. A function is created with an expression that starts with the keyword function
    . Functions have a set of parameters (in this case, only x) and a body, which
    contains the statements that are to be executed when the function is called.

Eg: the name of the function = function(x) {what to execute to x}

  1. Var is global and let is local.

  2. 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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#1193

How can you create a function in Javascript? A function starts with let or const then the name of the function and then 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. The body of the function muss be wrapped in { }.

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

var are visible throughout the whole function that they appear in—or throughout the global scope.

Let is in fact local to the block that its’s declared in

What is a pure function?
Pure functions are functions that accept an input and returns a value without modifying any data outside its scope. Its output or return value must depend on the input/arguments and pure functions must return a value.

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#1194
  1. How can you create a function in Javascript? -
    a) define a const to hold a function value
    b) declare a function
  2. What is the difference between var and let in regards to scope? -
    let defines the binding locally, whereas var is globally
  3. What is a pure function? -
    no side effects are produced. The function output is always the same for a given input.
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#1195

1. How can you create a function in Javascript?

Start with the keyword function --> naming the function --> ( ) may or may not have a set of parameters --> open the curly braces --> code to be executed.

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

"Bindings declared with let and const are in fact local to the block that they are declared in, so if you create one of those inside of a loop, the code before and after the loop cannot “see” it “ - JS

Scope means where these variables are available for use. Some declarations are either globally scoped or function/locally scoped. Var is a global binding and let is a local binding.

So a variable declared in a block with let is only available for use within that block and not outside of that block.

3. What is a pure function?

Given the same input, it will always return the same output with no side effects.

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#1196
  1. How can you create a function in Javascript?
    Functions are created with the keyword at the beginning, followed by a set of parameters and a body that contains the statements that are to be executed
  2. What is the difference between var and let in regards to scope?
    Let bindings are only local to the block they are defined in, thus the code before and after the loop it is located in cannot see it. The var binding is visible throughout the entire function they appear in (global scope)
  3. What is a pure function?
    A pure function has no side effects and doesn’t rely on side effects from other codes as well. It produces the same value when called upon time and time again.
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#1197
  1. Use the following format:
    nameOfFunction = function(x) {
    body of function;
    };
  2. Bindings declared with let and const are local to the block (wrapped in braces) that they are declared in, so if you create one of those inside of a loop, the code before and after the loop cannot “see” it. In pre-2015 JavaScript, only functions created new scopes, so old-style bindings, created with the var keyword, are visible throughout the whole function that they appear in—or throughout the global scope, if they are not in a function.
  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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#1198

Functions are crated with expressions that start with a pre defined keywork. They are used to embody a set of parameters and to be executed when they are called upon.

Let is recognised by block in which variables are declared and var is dif by all the programme.

A pure function is a function that exists on it’s own without any side effects, and without being influenced by any side effects.

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#1199

1. How can you create a function in JavaScript?
A function is created using the function keyword followed by the variable name and brackets.

2. What is the difference between var and let in regards to scope?
When we use the keyword “var”, the variable is inside the scoop of the function. Using the keyword “let” means that it will only be seen inside of the block.

3. What is a pure function?
This function has no side effects and if it is passed a parameter it will always return the same value. Meaning, no other functions can change it.

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#1200
  1. By utilizing a keyword const and name the function and create a normal program so that the function will execute it. ex: const B = function(x,y) { return ((x+8)*9-y)/2;}
    console.log(B(142,90));
  2. The let can only be see inside the block(brackets ,parentheses, bracelet) in which it was put inside the function, and for a variable it is see in the whole function and even globally if they are not in a function.
  3. It is having the same input and always receiving the same output no matter what and whit no side effect like, hash function.
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#1201
  1. with a declaration or a function expression
  2. var is function scope, let is block scopes
  3. one that has an relies on no side-effects
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#1202
  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 (in this case, only x) and a body, which
    contains the statements that are to be executed when the function is called with {}
  2. What is the difference between var and let in regards to scope?
    let and const are in fact local to the block that they
    are declared in, so if you create one of those inside of a loop, the code before and
    after the loop cannot “see” it. The var keyword, are visible
    throughout the whole function that they appear in—or throughout the global
    scope, if they are not in a function.
  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.
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#1203
  1. How can you create a function in Javascript?

A function definition is a regular binding where the value of the binding is a function.
f.x. if we wanted to create a square function, where you would put your input and then it would be squared.

const square = function(x) {
  return x * x;
};

console.log(square(12));
// → 144
  1. What is the difference between var and let in regards to scope?

let and const use its own local environment, which means when used in a loop the code before and after wont be able to see that code while var on the other hand defines it globally meaning the the variable stays.

  1. 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. A pure function has the special property that, when called with the same arguments, it always produces the same value.

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#1204

A function is declared using the “function” keyword, followed by the function name, followed by parentheses (). We want to name a function the same way we would name a variable; use a descriptive name that describes the purpose of it, e.g., “addNumbers” to name a function that is programmed to add numbers. The body of the function is written within curly brackets - { } -.
In Javascript, both “var” and “let” are used to declare variables. The “let” keyword was used in the later version of Js knows as ES6(ES2015). It is the preferred way to declare variables. The “var” variable is a functioned scope and can only be accessed inside of its given function while the “let” variable is a block-scoped variable meaning that it can be accessed only from within the if-block statement.
Another key difference in terms of scope of the keywords “var” and “let” is being able to redeclare the values of the variables when using the keywords respectively. When using the keyword “var”, you are able to change the global value of a variable from within a block but when using the keyword “let”, you are only able to change the value of a variable within its reach. For example, if you use “let” to change the value of a variable within a block, its value is changed only within that specific block, and it is treated as a different variable. Meaning that it retains the value that was assigned to it using “let” outside of that given block and the new value given to that same variable using “let” is as if it were assigned to a completely different variable, even if it is using the same identifier, “a” used globally with a value and “a” used locally (block-scoped) which is treated as a new and different variable.
A deterministic function (or pure function) will always produce the same output for a particular input, it 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. A pure function has the pleasant property that, when called with the same arguments, it always produces the same value and doesn’t do anything else.

2021-04-30T02:21:00Z

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#1205
  1. How can you create a function in Javascript? by using the word “const” followed by the name of your function, then an equal sign and your variables.
  2. What is the difference between var and let in regards to scope? var is available with the entire fuction, vs let is readable only within the block.
  3. What is a pure function? a function that produces a value and not a side-effect, and also does not really on side-effects from other parts of the code to produce its value.
1 Like
#1206

  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 executed when the function is called.

  2. What is the difference between var and let in regards to scope?
    The difference between var and let keywords in regards to a scope is that the the let is not visible throughout the whole global scope where as var is visible throughout the whole function they appear in or throughout the global scope, if they are not in a function.

  3. What is a pure function?
    A purer function is a value producing function that does have side effects and does not rely on side effect from other code. Basically a pure function has a unique property that when called upon with the same arguments it always produces the same value. and does not do anything else.

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#1207

  1. How can you create a function in Javascript?
    I can create my own function with keyword function followed by the name of the function. After the function name, open and close parentheses. After parenthesis, open and close curly braces. Within curly braces, I can write lines of code.
    The function keyword can be used as an expression and create a function value. Or can be used as a statement and can be used to declare a binding and give it a function as its value.

  2. What is the difference between var and let in regards to scope?
    var variables are “function scope” which means they are only available inside the function they are created in, or if not created inside a function, they are “globally scoped”.
    let variable rather then being scoped to the nearest function, they are scoped to the block (block is a set of opening and closing curly brackets).

  3. What is a pure function?
    A pure function is a function which given the same input, will always return the same output and produces no side effects.

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#1208

  1. Function in JavaScript could be created with keyword “function”. Afterwards you can program function with set of parameters, that are executed, when function is called.

  2. let is readable only within the block and var is readable alongside entire function

  3. Pure function is one which produces a value, not a side effect. And also this function does not rely on side effects of other code. I always produces the same value.

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