Day17.md

#Day 17

##Jason

###Scope

• global variables can be declared outside of and refferred inside of functions. (unlike PHP).
• The reverse is not true. Variables defined inside functions cannot be seen outside the function.
• Global functions can be manipulated inside of a function
• Functions can also be called before the function was actually created.

####Hoisting Anything declared with var is subject to hoisting. BEWARE OF ACCIDENTAL HOISTING

Functiom creation

function function_name() {
	code...;
}

or

	code...;
}

####IIFE

(function() {
	code...;
})();

this function will run itself!! Note the syntax

###Arrays

var array = [...];

####Length of Arrays array.length will give you the length of the array No such thing as associative arrays in JS.

###For Each

array.forEach(function(element,index,array){
	code...;
});

##Ben

####Adding elements array.push(element): puts element at the end of array array.pop(): takes the last element off the array. returns element popped value array.unshift(element): puts element at the beginning of the array array.shift(): takes the first element off the array

####Finding elements within arrays array.indexOf(element): returns the index of the element. -1 if not found

####Splice array.splice(element,num): removes the num of elements starting at element parameter. array.splice(element1,0,element2): adds element2 before element1. array.splice(element1,1,element2): replaces element1 with element2.

• Splice isn't limited by the number of insertions or deletions you want to do.

####Other Stuff

• array.reverse() : reverses the array;
• array.sort() : sorts array alphabetically (or with methods).

Method Nesting

• You can nest methods into a chain i.e. array.reverse().sort().

####Join array.join(glue) : same function as implode PHP.

####Splitting array.split(delimeter) : same function as implode in PHP.