Parsing small string

Jaspersan has asked for the wisdom of the Perl Monks concerning the following question:

Greeting Monks,
I need to parse data like this: .command parameter
Here is what I got so far:

#!/usr/bin/perl
#get command portion of data
use strict;

my ($stripped,$cmd,$cmd_loc,$cmd_locend);
    
$stripped = ".command parameter";
$cmd_loc=index($stripped,".");
$cmd_locend=index($stripped,chr(32));
$cmd=substr($stripped,$cmd_loc,$cmd_locend++);

print $cmd."\n";
[download]

This works just fine, but when I try to check if there is no parameter (I know it has to do with the chr(32), since there would be no space if it was only a command :P), but all the attempts to check for this have failed. I've tried checking to see it $cmd_locend == -1, etc.

I know this is a simple problem, but I guess I've been looking at the code to long, and have lost sight of it :\. Any help will be greatly appreciated!
Thanks
^jasper <jasper@wintermarket.org>

Title edit by tye

Comment on Parsing small string Select or Download Code

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Re: Parsing by VSarkiss (Monsignor) on Jun 11, 2002 at 15:10 UTC
You don't have to inch along the string (you're used to programming in C, right? ;-) If the command and optional parameter are alphanumeric, just do this: `if ($stripped =~ /\.(\w+)\s+(\w*)$/) { ($cmd, $parameter) = ($1, $2); # Other stuff.... }` [download] In general, if you want to take a string apart in Perl, regexes are much easier. More info at perlop (look for "quote-like operators") and perlre. HTH	[reply] [d/l]
Re: Re: Parsing by Jaspersan (Beadle) on Jun 11, 2002 at 15:45 UTC
I was thinking about using regex, but havnt read much about it. Thanks for the help. p.s: ive never touched C :P ^jasper <jasper@wintermarket.org>	[reply]
Re: Parsing by Joost (Canon) on Jun 11, 2002 at 15:09 UTC
You could also try using a regex for this: `my ($cmd,$param) = ($stripped =~ /\.(\S+)\s(\S)/);` [download] `-- Joost downtime n. The period during which a system is error-free and immune from user input.` [download]	[reply] [d/l] [select]
Re: Parsing by Jaspersan (Beadle) on Jun 11, 2002 at 15:05 UTC
Ha, Just after I posted the first question I fix the problem :P. Oh well... Reply if you wish (if you can give me some pointers). Here is the 'fixed' code: `#!/usr/bin/perl use strict; my $stripped = ".command"; my $cmd; my $cmd_loc=index($stripped,"."); my $cmd_locend=index($stripped,chr(32)); if ($cmd_locend > 1) { $cmd=substr($stripped,$cmd_loc,$cmd_locend++); } else { $cmd=substr($stripped,$cmd_loc); } print $cmd."\n";` [download] God I feel stupid now :) ^jasper <jasper@wintermarket.org>	[reply] [d/l]