Re: map a list

use strict;
use warnings;

my $str = "a,b=c,e=#f";

my @result = map {
    /(\w+)(=(#?)(\w+))?/;
    defined $3 && $3 eq '#' ? "$1=>fn($4)" :
    defined $2 ? "$1=>$4"
               : "$1=>fn($1)"
    } split ',', $str;

print "@result";
[download]

Prints:

a=>fn(a) b=>c e=>fn(f)
[download]

DWIM is Perl's answer to Gödel

Comment on Re: map a list Select or Download Code

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Re^2: map a list by merlyn (Sage) on Mar 12, 2007 at 20:38 UTC
`/(\w+)(=(#?)(\w+))?/; defined $3 && $3 eq '#' ? "$1=>fn($4)" :` [download] Danger! if that regex match fails, you're getting the previous round's information. GrandFather, I thought you knew better. :( -- Randal L. Schwartz, Perl hacker	[reply] [d/l]
Re^3: map a list by GrandFather (Saint) on Mar 12, 2007 at 21:00 UTC
Argh, I did know better, I just forgot. However that's not a style I'd recommend for practical code in any case - it would be a dog to maintain and is somewhat obscure. Inserting `die if !` in front of the regex might suit the OP's purpose. DWIM is Perl's answer to Gödel	[reply] [d/l]
Re^2: map a list by evil_otto (Novice) on Mar 12, 2007 at 19:31 UTC
Ah! While this answer is not ideal (it doesn't preserve the case : action style of the original, which makes it more straightforward to add in another syntax when that becomes necessary), it did provide the insight for achieving wisdom: since I'm already matching the expression with a RE, I can simply use the work already done and avoid re-splitting. So: `my @result=map { /(\w+)=#(.+)/ ? ($1,fn($2)) : /(\w+)=(.+)/ ? ($1, $2) : ($_, fn($_)) } split(/,/, $str);` [download] Thanks. Still curious about that segfault tho...	[reply] [d/l]
Re^3: map a list by GrandFather (Saint) on Mar 12, 2007 at 19:38 UTC
Depending on what the larger problem is, you may be better looking at something like Parse::RecDescent. Even if you stick to manual parsing, using a more explicit coding structure as shown in dragonchild's example would pay off in terms of maintenance. DWIM is Perl's answer to Gödel	[reply]