String trim, snip, collapse in Perl

Post as a follow-up to Perl, Trim White Space from a String. I’m posting this so there is something a bit more idiomatic out there and make sure to get the message out: don’t use prototypes in Perl. Except for the rarest case the only reasonable use for them is to accept code blocks as arguments and that has nothing to do with the following.

#!/usr/bin/env perl

sub trim {
    my @trim = @_;
    s/\A\s+|\s+\z//g for @trim;
    @trim;
}

sub ltrim {
    my @trim = @_;
    s/\A\s+// for @trim;
    @trim;
}

sub rtrim {
    my @trim = @_;
    s/\s+\z//g for @trim;
    @trim;
}

sub collapse {
    my @trim = @_;
    s/\A\s+|\s+\z//g for @trim;
    s/\s{2,}/ /g for @trim;
    @trim;
}

my @samples =
    ( "   This is simple.   ",
      "No leading or trailing.",
      "French spacing.  Please.",
      " \t\nOH\t\t\t\n\n\nHAI  \t   ",
    );

print "TRIM:\n",
    join("\n",
         map { qq{-->$_<--} } trim(@samples)
         ),
    "\n\n";

print "LTRIM:\n",
    join("\n",
         map { qq{-->$_<--} } ltrim(@samples)
         ),
    "\n\n";

print "RTRIM:\n",
    join("\n",
         map { qq{-->$_<--} } rtrim(@samples)
         ),
    "\n\n";

print "COLLAPSE:\n",
    join("\n",
         map { qq{-->$_<--} } collapse(@samples)
         ),
    "\n\n";

Yields–

TRIM:
-->This is simple.<--
-->No leading or trailing.<--
-->French spacing.  Please.<--
-->OH			

HAI<--

LTRIM:
-->This is simple.   <--
-->No leading or trailing.<--
-->French spacing.  Please.<--
-->OH			

HAI  	   <--

RTRIM:
-->   This is simple.<--
-->No leading or trailing.<--
-->French spacing.  Please.<--
--> 	
OH			

HAI<--

COLLAPSE:
-->This is simple.<--
-->No leading or trailing.<--
-->French spacing. Please.<--
-->OH HAI<--