Hello monks,

I got a small problem concerning references in perls regex flavor.
For example, I got a string like this

$lala = "Hello you therre."

And I want to match all double characters (a-z), i.e. ll and rr in the given string and contract them to one char. (Please do not take this seriously, its just an example.)

So I went like this:

$lala =~ s/([a-z])$1/$1/g

It does not work. So I played around:

$lala =~ s/([a-z])\1/$1/g

This works. But what I kept in mind was this: Warning on \1 vs $1

So I don't know why in the first version the $1 in the matching part (not the substitute part) does not work but with \1 in the second version? I thought \1 is obsolete and just a relic of a sed styled referencing.

This is nothing big, but ... did I miss something?

Thanks in advance,

ocs.

tennis players have fuzzy balls.

In reply to perl regex referencing by ocs

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