split in Ruby

String objects in Ruby have a method called split. It is similar to the split function of Perl. It can cut up a string into pieces along a pre-defined string or regex returning an array of smaller strings.

In the first example you can see how to split a string every place where there is a comma ,:

require 'pp'

words_str = 'Foo,Bar,Baz'
words_arr = words_str.split(',')
pp words_arr   # ["Foo", "Bar", "Baz"]

In the second example we use a Regex to match the places where we would like to cut up the string. It makes the splitting much more flexible:

require 'pp'

words_str = 'One   -  Two-  Three'
words_arr = words_str.split(/\s*-\s*/)   # ["One", "Two", "Three"]
pp words_arr

Split with limit

We can pass a second parameter to split that will limit the number of reurned valus. If we pass 3, then split will make two cuts and return the results:

require 'pp'

words_str = 'Foo,Bar,Baz,Moo,Zorg'
words_arr = words_str.split(',', 3)
pp words_arr   # ["Foo", "Bar", "Baz,Moo,Zorg"]

Split by empty string

As a slightly special case, if we use an empty string (or empty regex) to split with, then we will get back an array of the individual characters:

require 'pp'

words_str = 'Foo,Bar,Baz'
words_arr = words_str.split('')
pp words_arr   # ["F", "o", "o", ",", "B", "a", "r", ",", "B", "a", "z"]

timestamp: 2015-10-31T12:00:01