Date: Fri, 28 Apr 2006 03:20:16 +0300 From: Giorgos Keramidas <keramida@ceid.upatras.gr> To: Gary Kline <kline@tao.thought.org> Cc: freebsd-questions@freebsd.org, Arne Skjaerholt <arnsholt@broadpark.no> Subject: Re: scripting languages... Message-ID: <20060428002016.GB1742@gothmog.pc> In-Reply-To: <20060427235828.GD2601@thought.org> References: <20060427024158.GA71123@thought.org> <20060427031043.GA69851@gothmog.pc> <20060427214854.GA2601@thought.org> <1146188104.7085.8.camel@bursar> <20060427235828.GD2601@thought.org>
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On 2006-04-27 16:58, Gary Kline <kline@tao.thought.org> wrote:
> > Getting at argv/argc is actually pretty simple in Perl. The global array
> > @ARGV contains the arguments given on the command-line, but not the name
> > of the file (this datum is contained in $0). Therefore your argv[1] in C
> > is $ARGV[0] in Perl. The number of command-line arguments can be
> > obtained in two ways, either you interpret the array in a scalar context
> > and get its length: ``my $argc = scalar @ARGV'' or you use the last
> > index of the array and add one: ``my $argc = $#ARGV + 1''. Of course, in
> > most cases you'll just want to loop over the command-line args, so a
> > foreach loop should suffice, or of course one of the Getopt (Getopt::Std
> > or Getopt::Long in most cases) modules.
>
> So, could I say:
>
> my $argc = $#ARGV+1; $count = 0;
> while ($argc--)
> {
> if (! (checkErr($ARGV[$count], $count)))
> {
> printf("Processing %s\n", $ARGV[$count]);
> doWhatever($ARGV[$count]);
> }
> $count++;
> }
>
> or something close-to!?
I believe the idiomatic way of doing this would be something more like:
foreach $arg (@ARGV) {
if (!checkErr($arg)) {
printf("Processing %s\n", $arg);
doWhatever($arg);
}
}
Your version may work too, but I'm always wary of all the index
trickery involved in handling $#ARGV fearing it may easily lead to
off-by-one bugs. So I prefer foreach() loops :)
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