ruby operator "=~"

ruby operators
kamen raider picture kamen raider · Apr 25, 2011 · Viewed 89.8k times · Source

In ruby, I read some of the operators, but I couldn't find =~. What is =~ for, or what does it mean? The program that I saw has

regexs = (/\d+/)
a = somestring
if a =~ regexs

I think it was comparing if somestring equal to digits but, is there any other usage, and what is the proper definition of the =~ operator?

Answer

Mike Lewis picture Mike Lewis · Apr 25, 2011

The =~ operator matches the regular expression against a string, and it returns either the offset of the match from the string if it is found, otherwise nil.

/mi/ =~ "hi mike" # => 3 
"hi mike" =~ /mi/ # => 3 

"mike" =~ /ruby/ # => nil

You can place the string/regex on either side of the operator as you can see above.

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