Re: sorting based on a list

If you are really going to sort by the first letter only in a special order you might try it with this:

my $sortstr = join('', @list);
my @sorted_list = sort {
    index($sortstr,substr($a,0,1)) <=> index($sortstr,substr($b,0,1))
        ||
        $a <=> $b
    } @list2;
[download]

The first will compare the first letter only, the later will compare if the first letter is equal.
--
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Comment on Re: sorting based on a list Download Code

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Re: Re: sorting based on a list
by ChemBoy (Priest) on May 09, 2001 at 19:05 UTC

Nice idea--I propose the following modification, to dump extra words at the end (and to use string comparison, of course):

my $sortstr = join('', @list);
my @sorted_list = sort {
 rindex($sortstr,substr($b,0,1)) <=> rindex($sortstr,substr($a,0,1))
        ||
        $a cmp $b
    } @list2;
[download]

Of course, you might want words that start with letters not in the list to be at the front, in which case, alphie's solution is preferable (aside from using <=> instead of cmp).

Update: doh! It doesn't do what I thought it did! Fix coming...
Fix here:

my $sortstr = join('', @list);
my @sorted_list = sort {
    my ($tmp1,$tmp2);
 (($tmp1 = index($sortstr,substr($a,0,1))) >= 0 ? $tmp1 : length($sort
+str))
    <=> 
 (($tmp2 = index($sortstr,substr($b,0,1))) >= 0 ? $tmp2 : length($sort
+str))
        ||
        $a cmp $b
    } @list2;
[download]

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