Removing spaces between single letters

Question

I have a string that may contain an arbitrary number of single-letters separated by spaces. I am looking for a regex (in Perl) that will remove spaces between all (unknown n

Answer 1

It's not a regex but since I am lazy by nature I would it do this way.

#!/usr/bin/env perl
use warnings;
use 5.012;

my @strings = ('a b c', 'ab c d', 'a bcd e f gh', 'abc d');
for my $string ( @strings ) {
    my @s; my $t = '';
    for my $el ( split /\s+/, $string ) {
        if ( length $el > 1 ) {
        push @s, $t if $t;
        $t = '';
        push @s, $el;
        } else { $t .= $el; }
    }
    push @s, $t if $t;
    say "@s";
}

OK, my way is the slowest:

no_regex   130619/s         --       -60%       -61%       -63%
Alan_Moore 323328/s       148%         --        -4%        -8%
Eric_Storm 336748/s       158%         4%         --        -5%
canavanin  352654/s       170%         9%         5%         --

I didn't include Ether's code because ( as he has tested ) it returns different results.