Re: printing enviroment vars from regex

RnC,
This is basic implementation that you can expand as you see fit. It is pretty fragile in the assumptions which means you will have to add your own error handling.

#!/usr/bin/perl
use strict;
use warnings;

for my $file ( @ARGV ) {
    if ( ! open(INPUT, '<', $file) ) {
        warn "Unable to open $file - skipping!\n";
        next;
    }
    while ( <INPUT> ) {
        print and next if ! /\$\w+/;
        $_ =~ s/\$(\w+)/$ENV{$1}/g;
        print;
    }
}
[download]

Cheers - L~R

Comment on Re: printing enviroment vars from regex Download Code

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Re^2: printing enviroment vars from regex by BUU (Prior) on Aug 01, 2004 at 19:43 UTC
`$_ =~ s/\$(\w+)/$ENV{$1}/g` I'm pretty sure you want: `0 while $_ =~ s/\$(\w+)/$ENV{$1}/;`	[reply] [d/l] [select]
Re^3: printing enviroment vars from regex by Limbic~Region (Chancellor) on Aug 01, 2004 at 19:46 UTC
BUU, Well saying that without an explanation doesn't help me much. Of course it is possible it should be obvious to me why - but I am dense (to be read it is the weekend). It worked fine for my sample input - what advantages does yours have over mine? Cheers - L~R	[reply]
Re^4: printing enviroment vars from regex by Aristotle (Chancellor) on Aug 01, 2004 at 19:54 UTC
His version will do nested replacements, eg if `$FOO` expands to the text `$BAR`, then that will in turn be expanded as well. I don't know if that's particularly desirable, though. Makeshifts last the longest.	[reply]
Re^5: printing enviroment vars from regex by Limbic~Region (Chancellor) on Aug 01, 2004 at 20:02 UTC
Re^6: printing enviroment vars from regex by Aristotle (Chancellor) on Aug 01, 2004 at 20:15 UTC