Concatenating file name in Perl script

So a co-worker of mine asked me to write a script/program to rename 150 files! :eek:

I got the gist of it done... however, when I try to put 3 variables together to form a part of a new file name using the following syntax, I can't get it to work...

my $final = "$a1" . "" . "$a2" . "m" . "$d3" . "e";

so if $a1 = peter, $a2 = paul, and $d3 = mary, I want $final to be "peterpaulmmarye". :D Concatenating is done using "." operator I thought... however, with or without quotes around the variables, I keep getting

Global symbol "$a2" requires explicit package name at rename.pl line 33.

error messages... :( Any help would be appreciated...

Have you tried using the 'join' command?
$final = join "", "$a1", "", "$a2", "m", "$d3", "e";

That's an awesome command! :D
However, it still gives me the same error message... :(

In previous lines, I define it by if statements...

if ($d1 eq '540') {my ($a1) = 'lq'};
if ($d1 eq '680') {my ($a1) = 'mq'};
if ($d1 eq '819') {my ($a1) = 'hq'};

are those wrong? Still clueless... trying to learn Perl is such a pain... but thanks for the help rock. :)

Ok... turns out I had to declar those two ($a1 and $a2) globally first. :p

Thanks rock, again, for that awesome command "join"!! :D I'd never would have seen that coming!

Glad to be of help! I haven't written any Perl for a year or more, but I knew I did concatenation then and pulled up some of that source -- and there it was. Interestingly, I had no idea "." was an option ;)

Why is the second string null? What's the purpose of that?

Quote:

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Originally Posted by JPnyc

Why is the second string null? What's the purpose of that?

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that's because "join" works like "split" in that it uses the first string to join all of the others, and since I didn't want anything else inbetween, null string is the way to go! :)