method
=~
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=~(p1)
public
Match—If obj is a Regexp, use it as a pattern to match against str,and returns the position the match starts, or nil if there is no match. Otherwise, invokes obj.=~, passing str as an argument. The default
~ in Object returns nil.
Note: str =~ regexp is not the same as regexp =~ str. Strings captured from named capture groups are assigned to local variables only in the second case.
"cat o' 9 tails" =~ /\d/ #=> 7 "cat o' 9 tails" =~ 9 #=> nil