hi monks,

I have a small perl6 program that basically rename all files in a directory, according to a given regex

I stuggled some time to get it work because I was using the match variable ($/) to do the filename replacement whereas I should have used the topic variable ($_)

This seems to me very conter-intuitive however. Could someone explain why I can't use $/ in this program ?

here's the code of the original version (doesn't works but if you replace $/[0] by $_[0] it magically works!)

#!/usr/bin/perl
use v6;

my Int $files_renames_count = 0;

for dir(".") -> IO::Path $current_file {
    
    my Str $cur_filename = $current_file.basename;
    
    next if $cur_filename.IO ~~ :d; #skip directories (see http://doc.
+perl6.org/type/IO)
    
    my Str $new_filename =  $cur_filename.subst(
        /(.+)\.txt/,
        { $/[0] ~ " (2).txt" },    # doesn't works :( $/[0] is always 
+empty
                                # works with $_[0] however (???)
        :i # case insensitive replacement
    );    
    if ($new_filename ne $cur_filename)  {
        if ($new_filename.IO ~~ :e) {
            say "skipping file $cur_filename : $new_filename already e
+xists";
        } else {
            say "renaming $cur_filename in $new_filename";
            rename $cur_filename, $new_filename;
            $files_renames_count++;
        }
    }
}
say "$files_renames_count files renammed";

[download]

i use perl6 version 2014.08-284-gfcdf308 built on MoarVM version 2014.08-108-g93d47dd

my OS is Windows7

In reply to perl6 match variable by jeckyhl

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