'Extract a substring from a string in Ruby using a regular expression

How can I extract a substring from within a string in Ruby?

Example:

String1 = "<name> <substring>"

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

rubyregexstringsubstring


Solution 1:[1]

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

No need to use scan, if we need only one result.
No need to use Python's match, when we have Ruby's String[regexp,#].

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

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

Solution 2:[2]

You can use a regular expression for that pretty easily…

Allowing spaces around the word (but not keeping them):

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

Or without the spaces allowed: 

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

Solution 3:[3]

Here's a slightly more flexible approach using the match method. With this, you can extract more than one string:

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"

Solution 4:[4]

A simpler scan would be: 

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

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1
Solution 2 Sergio Tulentsev
Solution 3 Grant Birchmeier
Solution 4 Alan Moore

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