Re: Difference between $1 and \1.

[LanX]

> Can anyone explain this behaviour ?

Google finds plenty of them by entering your title:

Perl Difference between $1 and \1

Now what are your problems left?

Within the matching part of regexes $1 can't be used for your purpose!

It's still bound to the match of the last regex:

  DB<107> $_="a"; /(\w)/; $_='aaa'; /($1+)/; print $1
aaa

And regexes are older than Perl, \1 was the usual way to address first match, but variables with $-sigils belong to the syntax of scripting languages like Perl.