I always figured, if you're going to do it, do it right:
#!/usr/bin/perl
use strict;
my $pattern = shift @ARGV;
my ($src, $dest) =
($pattern =~ m/^s(.)([^\1]*)\1([^\1]*)\1$/)
or die "1st arg not s/// construct (or construct too complicated)"
+;
my %to_rename;
for my $f (@ARGV) {
(! -e $f) && die "$f does not exist; $!";
my $n = $f;
$n =~ s/$src/$dest/;
( -e $n or defined $to_rename{$n})
&& die "$f would be renamed to $n; clobber detected";
$to_rename{$n} = $f;
}
while (my ($n, $f) = each %to_rename) {
rename $f, $n or warn "Cannot rename $f to $n; $!";
}
OK, I can see bad style there, but it works. I wrote it some time ago...
I called the script ~mv, and it is called as ~mv s/\.old$/.new/ *.old