Perl regex extracting a match using braces -


i tested following code

#! /usr/bin/perl   use strict; use english;  #this code extracts current scripts filename  #by removing path filepath  $script_name = $program_name;  ${script_name} =~ s/^.*\\//; #windows path  #${script_name} =~ s/^.*\///; #unix based path  print $script_name;

and don't understand why these braces extract match without using /r modifier. can explain why , how works or point me documentation?

you're getting little confused!

the braces make no difference. ${script_name} identical $script_name.

you code first copies entire path script file $program_name $script_name.

then substitution removes , including last backslash, leaving file name.

the /r modifier used if wanted modify 1 string , put result of modification another, write code in 1 step as

$script_name = $program_name=~ s/^.*\\//r

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