Dear monks,

Today I'm trying to define a regex substitution from a parameter which is received from outside.

In the s/<regex>/<replacement>/ structure, both the <regex> and the <replacement> are passed from other strings.

Seems the <regex> part works well, however for the <replacement> part, there is a '$1' to capture what's matched from the <regex> part and this seems not working.

In fact, it looks like the '$1' was not interpretted at all.

 

My script is like the following:

$a = 'https://www.domain.com/aaa/bbb/file.zip';

$from = 'aaa.*\/(.+)$';
$to   = 'file_publish?file=$1';

$a =~s/$from/$to/i;

print "\$1:  $1\n";

print "RESUTL: $a\n";

[download]

 

The result is like:

> ./pt_demo.pl
$1:  file.zip
RESUTL: https://www.domain.com/file_publish?file=$1

 

But what I need is to replace the '$1' with the actual file name 'file.zip', so the result I actually need is like:

RESUTL: https://www.domain.com/file_publish?file=file.zip

 

My monks, could you please cast your light of wisdom on me to help me get the '$1' work regex substitution?

 

My best wishes

In reply to Define regex substitution $1,$2,... from a string by sylph001

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