Check whether a string contains one of multiple substrings
Ruby on-RailsRubyStringRuby 2.1Ruby on-Rails Problem Overview
I've got a long string-variable and want to find out whether it contains one of two substrings.
e.g.
haystack = 'this one is pretty long'
needle1 = 'whatever'
needle2 = 'pretty'
Now I'd need a disjunction like this which doesn't work in Ruby though:
if haystack.include? needle1 || haystack.include? needle2
puts "needle found within haystack"
end
Ruby on-Rails Solutions
Solution 1 - Ruby on-Rails
[needle1, needle2].any? { |needle| haystack.include? needle }
Solution 2 - Ruby on-Rails
Try parens in the expression:
haystack.include?(needle1) || haystack.include?(needle2)
Solution 3 - Ruby on-Rails
You can do a regex match:
haystack.match? /needle1|needle2/
Or if your needles are in an array:
haystack.match? Regexp.union(needles)
(For Ruby < 2.4, use .match without question mark.)
Solution 4 - Ruby on-Rails
(haystack.split & [needle1, needle2]).any?
To use comma as separator: split(',')
Solution 5 - Ruby on-Rails
For an array of substrings to search for I'd recommend
needles = ["whatever", "pretty"]
if haystack.match?(Regexp.union(needles))
...
end
Solution 6 - Ruby on-Rails
To check if contains at least one of two substrings:
haystack[/whatever|pretty/]
Returns first result found
Solution 7 - Ruby on-Rails
Use or instead of ||
if haystack.include? needle1 or haystack.include? needle2
or has lower presedence than || , or is "less sticky" if you will :-)
Solution 8 - Ruby on-Rails
I was trying to find simple way to search multiple substrings in an array and end up with below which answers the question as well. I've added the answer as I know many geeks consider other answers and not the accepted one only.
haystack.select { |str| str.include?(needle1) || str.include?(needle2) }
and if searching partially:
haystack.select { |str| str.include?('wat') || str.include?('pre') }