Re^2: Convert a string into a hash

Ok, I am going to go "crazy" here and ask why you want a hash in the first place?

I just want to iterate the elements of another list of tokens, but in the same order them appear in the main list of tokens. Simplified:

my $tokens = "32,15,4,72,13,28,14";
my %code = do { my $i = 0; map { $_ => $i++ } split /,/, $tokens };

my $list = "4,13,15";
my $ok;
for my $token (sort { $code{$a} <=> $code{$b} } split /,/, $list) {
  print "$token ";
  # more code with $token...
  last if $ok;
}

__END__
15 4 13
[download]

Obviously, both $tokens and $list are dynamically loaded from somewhere else...

Comment on Re^2: Convert a string into a hash Download Code

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Re^3: Convert a string into a hash by Marshall (Canon) on Aug 15, 2009 at 07:05 UTC
This is a straight-forward implementation. Post again if I didn't get it right.... `#!/usr/bin/perl -w use strict; my $tokens = "32,15,4,72,13,28,14"; my @tokens = split (/,/, $tokens); my $list = "4,13,15"; my @list = split (/,/,$list); my %list = map {$_ => 1}@list; my @ordered_nums = grep{$list{$_}}@tokens; print "@ordered_nums\n"; __END__ PRINTS: 15 4 13` [download]	[reply] [d/l]
Re^4: Convert a string into a hash by vitoco (Hermit) on Aug 15, 2009 at 16:29 UTC
That was the other aproach I thought, but the requirement changed to pick only the best token from $list, which is loaded many times based on some external events, while %code is initialized once. Based on the previous, I decided to keep that part, and now I want to rewrite: `my $best = 14; # actually, last value from $tokens. for my $b (split /,/, $list) { $best = $b if $code{$b} < $code{$best}; }` [download] Update: syntax error, extra ")"...	[reply] [d/l]
Re^5: Convert a string into a hash by Marshall (Canon) on Aug 18, 2009 at 17:47 UTC
but the requirement changed to pick only the best token from $list Can you define what "best" means? Give a text description and then several examples.	[reply]
Re^6: Convert a string into a hash by vitoco (Hermit) on Aug 18, 2009 at 21:22 UTC
Re^7: Convert a string into a hash by Marshall (Canon) on Aug 19, 2009 at 00:49 UTC
Re^3: Convert a string into a hash by Marshall (Canon) on Aug 15, 2009 at 07:18 UTC
Ooops, mess up and double post...sorry.... This is a straight-forward implementation. Post again if I didn't get it right.... `#!/usr/bin/perl -w use strict; my $tokens = "32,15,4,72,13,28,14"; my @tokens = split (/,/, $tokens); my $list = "4,13,15"; my @list = split (/,/,$list); my %list = map {$_ => 1}@list; my @ordered_nums = grep{$list{$_}}@tokens; print "@ordered_nums\n"; __END__ PRINTS: 15 4 13` [download] Update: I would perhaps replace "list" with "list_order". Matter of choice.	[reply] [d/l]