How to Use the "each" Method in Ruby on Rails

[? Music ?] [Treehouse presents] 0:00 [Quick Tips] [How to Use the "each" Method in Ruby on Rails with Jason Seifer] 0:02 Hi, I'm Jason. 0:05 In this Treehouse Quick Tip, we're going to talk about the each method in Ruby. 0:07 The each method is part of the enumerable mixin. 0:11 The each method lets you iterate over different objects 0:14 inside of an array-like structure. 0:18 The method takes a block which specifies 0:20 what will happen on each successive iteration in the loop. 0:23 Here's how the each method looks. 0:27 Right now, I'm in an irb session. 0:30 Let me create an array of a few different things. 0:33 I have an array with 3 different items in it right now: 0:40 dog, cat, and frog. 0:43 If I wanted to go through and print out each of the different items 0:46 in the array, it would be really easy to do using the each method. 0:49 Here's what it would look like. 0:54 Now, in order to call the each method, 1:07 first, I type out the name of the object I want to iterate over, 1:09 which in this case is the array variable. 1:13 Then I type a period, which calls a method, 1:16 and then the name of the method I want to call, 1:20 in this case, each. 1:23 From there, type out a space and the word do. 1:26 Do tells the Ruby interpreter 1:31 that we're going to expect a block. 1:33 Then I type another space, 1:36 and I put the word item inside of 2 vertical pipes. 1:39 Anything in between these pipes is an argument to the block 1:43 which was specified by the do keyword, 1:47 and these arguments are going to be available 1:50 inside of the block. 1:52 From there, I press enter, and I type out what I want to happen 1:55 to the item. 1:58 In this case, I'm only printing out what the item is. 2:00 You don't need to worry about modifying the original items 2:04 inside the block, because only a copy is sent in, 2:07 and anything that you do won't affect the original item in the array. 2:11 That was 1 quick use of the each method. 2:17 You could have as much code as you want inside of the block. 2:20 Just make sure to keep it readable. 2:24

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