[Petal] [PATCH] Petal::Hash::Var error on undef + misc

[Steve Purkis]

Hi all,

As the functionality introduced in my previous patches doesn't seem to 
have made it into the main distro, I've produced another patch for 
Petal which implements the main point of my previous patches -- a user 
controllable flag for error on undefined variables -- without the 
performance hit (see below).

The flag can be set as such:
	$Petal::Hash::Var::ERROR_ON_UNDEF = 0 || 1;

Though arguably it should be a class/instance var of the processor:
	my $tmpl = Petal->new->error_on_undef( 0 || 1 );

I don't mind implementing that if people prefer it.

The patch also has some better error reporting when you try to access 
vars you shouldn't.  And because I've been extremely lazy, it includes 
extra tests that were copied over from the last patch.  The more the 
merrier, I say.

The same benchmark script is included so you can all see I'm not on 
crack:

	% perl t/benchmark.pl

	        	Templates Processed /s
	Machine:	400MHz PPC	1.7 GHz x86
	v0.96:  	66.26/s   	308.36/s
	Patched:	63.74/s   	295.07/s

This indicates roughly a 4% decrease in performance, most likely due to 
the extra error reporting.  If that's not livable, please let me know 
and I'll rewrite it in assembler ;-).

Regards,
-Steve