Functions

Question 1

functions

Answer 1

• allows us to reuse blocks of code.
• Allows is to wrap blocks of code into REUSABLE packages.
• You call a function to execute the function. Similarly you run a program to execute its code.
• mini programs inside your program
• The main point of functions is to get rid of duplicate code

Question 3

Argument

Answer 3

• Value passed in the function call.
• The input to functions are arguments
• The output is the return value

Question 4

Parameter

Answer 4

• Variable(s) in between the function’s parentheses in the definition statement.

Question 5

return

Answer 5

• sends back a value
• can’t pass functions to variables without it.
• Stops the execution of a function. This feature of “return” is similar in operation to “break”
• Every function returns something, but if “return” is not explicitly used it always returns “undefined” after the output is printed

Question 6

Function Declaration vs. Function Expression

Answer 6

//function declaration 
function test1() {
    return xyz;
}
//function expression
var test1 = function() {
    return xyz;
}
• two ways to declare a function 
• if the latter is used if you pass a different value the function is lost

Question 7

Scope

Answer 7

• Context of what some code can be executed in
• if you define a variable inside a function it can only be used inside the function. This is also known as local variable.
• Variables that was declared outside the function can be accessed inside the function.

Question 8

Higher Order functions

Answer 8

• Any function that takes a function as an argument, returns a function or both.

setInterval(sing, 1000);  when you pass "sing" this way without () you passing the code so that setInterval will execute it. 
• setInterval(function(){
   //statement;
}); - used when you want to pass a function but don't know what it is yet.

Question 9

Call

Answer 9

run or execute a function