Extract substring from string in Ruby using regex

Question

How to extract a substring from a string in Ruby?

Example:

String1 = "<name> <substring>" 

I want to extract substring from String1 (i.e. everything within the last occurrence of < and > ).

Answer 1

 String1.scan( /<([^>]*)>/).last.first 

scan creates an array that for each <item> in String1 contains the text between < and > in a singleton array (because when used with groups containing regular expressions, scan creates an array containing captures for each match). last gives you the last of these arrays and first , then returns a string in it.

Answer 2

 "<name> <substring>"[/.*<([^>]*)/,1] => "substring" 

No need to use scan if we need only one result.
No need to use match if we have String[regexp,#] .

See: http://ruby-doc.org/core/String.html#method-i-5B-5D

Note: str[regexp, capture] → new_str or nil

Answer 3

You can use regex for this quite easily ...

Resolution of spaces around a word (but not their preservation):

 str.match(/< ?([^>]+) ?>\Z/)[1] 

Or without valid spaces:

 str.match(/<([^>]+)>\Z/)[1] 

Answer 4

Here is a slightly more flexible approach using the match method. In this case, you can extract more than one line:

 s = "<ants> <pants>" matchdata = s.match(/<([^>]*)> <([^>]*)>/) # Use 'captures' to get an array of the captures matchdata.captures # ["ants","pants"] # Or use raw indices matchdata[0] # whole regex match: "<ants> <pants>" matchdata[1] # first capture: "ants" matchdata[2] # second capture: "pants" 

Answer 5

The simplest scan would be:

 String1.scan(/<(\S+)>/).last