Re^2: Perl 'grammar'

why is

my $empl_name = shift;
my ($last, $first) = $empl_name=~/^([^,]+), (.+)/ or return undef;
[download]

preferred over

my ($last, $first) = /(.*), (.*)/ or return undef;
[download]

(or perhaps /(.*),\s*(.*)/ ?)

Comment on Re^2: Perl 'grammar' Select or Download Code

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Re^3: Perl 'grammar' by gamache (Friar) on Jan 09, 2008 at 16:26 UTC
Hell, why not `sub format_name_for_AD {/(.+), (.)/ ? $2.$1 : undef}`?	[reply] [d/l]
Re^4: Perl 'grammar' by WoodyWeaver (Monk) on Jan 09, 2008 at 20:09 UTC
Good point. You lose the uc bit, but its awfully tight. I think I was reacting more to the parameter unpacking. The sub is handed a compound, and the parameter is stored and then broken apart. I tend to think of that breaking as part of the unpacking process, so in essence get two params passed to the sub in a particular format, hence my "first" line produces those two variables. It all comes down to chasing errors, I suppose. I've gotten the habit of putting in a print (or warn) at subroutine entry with the parameters passed controlled by a debug variable. With the one-liner, you can't really do that. But then again, its so bloody simple, perhaps its not necessary. --woody	[reply]
Re^5: Perl 'grammar' by gamache (Friar) on Jan 10, 2008 at 18:10 UTC
I tend to write my subroutines in three parts: first, a preamble where I throw the passed args into named variables; second, all the guts; and last, the return value. I find it helps with extensibility (but only barely).	[reply]
Re^6: Perl 'grammar' by WoodyWeaver (Monk) on Jan 10, 2008 at 18:42 UTC
Re^3: Perl 'grammar' by Porculus (Hermit) on Jan 11, 2008 at 21:00 UTC
The two are not the same. Consider what happens when the sub is called as `format_name_for_AD($foo)`.	[reply] [d/l]
Re^4: Perl 'grammar' by WoodyWeaver (Monk) on Jan 12, 2008 at 21:58 UTC
Ah, $_ != $_[0]. I did not think of that.	[reply]