Dear monks

I have tried the following replacement script, which does not work.

$ more replace.pl 
#!/usr/bin/perl -w -pi.orig
s/(a)(b)/$1{$2}/g;

$ more test.txt
ab

$ ./replace.pl test.txt
Use of uninitialized value within %1 in substitution iterator at ./rep
+lace.pl line 3, <> line 1.
$ more test.txt
(an empty line)

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However, it works fine with an additional escaping backslash before the left brace: s/(a)(b)/$1\{$2}/g;. I suspect that $1{$2} is recognized as addressing an associative array, but I could not find any mention in the documentation about such an expansion in the substitution part of a RE. Could somebody tell me? Regards, Luc.

In reply to Brace in the replacement part of a regular expression substitution by luc.bouge

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