index tells you the position of $s2 in $s1. length tells you the length of $s2, which you need for telling substr where to start the extraction.

With 

perldoc -f index

[download]
etc., you get a description of these functions.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Re: Perl Substr by rovf
in thread Perl Substr by lddzjwwy

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