In ruby arrays and hashes can be termed collections.
Ruby each loop.
The for in loop calls the each method of the specified object.
In this example we check to see if the value of i is equal to 3.
This works exactly like the each method for an array object with one crucial difference.
Iterators return all the elements of a collection one after the other.
Executes code once for each element in expression.
A loop is the repetitive execution of a piece of code for a given amount of repetitions or until a certain condition is met.
The each loop is perhaps the most useful of all the loops.
The ruby each loop the ruby method each allows you to go over a list of items without having to keep track of the number of iterations or having to increase some kind of counter.
Ruby gives us ways to do this without writing a loop each time.
Ruby loops loops in ruby are used to execute the same block of code a specified number of times.
Like a while loop the condition x 11 is checked when entering the loop and each time the loop body executes.
If the condition is false the loop will continue to execute.
Some operations in computer programming are best served with a loop.
And if it is we call break which stops everything and gets out of the loop.
It s the ruby way of doing repeat until done.
Like the array these elements are placeholders that are used to pass each key value pair into the code block as ruby loops through the hash.
We will cover while loops do while loops and for loops.
Ruby while loop n x 1 end output.
Each loop will take a list of variables and run a block of statements for each of them.
This chapter details all the loop statements supported by ruby.
Arrays and hashes define the each method and many other ruby objects do too.
We will be discussing two iterators here each and collect.
1 2 3 each do i break if i 3 puts i end 1 2.
X 1 y 11 until x y do print x.
Syntax collection each do variable code end.
Those coming from an imperative language might be more familiar with the for loop.
The each loop.
Let s look at these in detail.
The each iterator returns all the elements of an array or a hash.
You could say that we re iterating over each item in the array.
As that iterator yields values the for loop assigns each value or each set of values to the specified variable or variables and then executes the code in body.
Live demo usr bin ruby for i in 0 5 puts value of local variable is i end here we have defined the range 0 5.
The simplest way to create a loop in ruby is using the loop method loop takes a block which is denoted by.
As we re looping through each item in the array we re using a specific pattern getting an item out of the array and working with it in a specific way.
For a hash you create two elements one for the hash key and one for the value.
