Hi Ronen, On Thursday 23 September 2010 13:46:55 Ronen Angluster wrote: > Hello all, >
first, a few comments about your code. > please consider the following code: > ################################### > package main; Always add "use strict;" and "use warnings;". Also see: http://perl-begin.org/tutorials/bad-elements/ > my $x= main::foo->new(); 1. my $x = foo->new(); would be enough here. 2. You should start namespaces with an uppercase letter. Namespaces starting with a lowercase letter are reserved for pragmas. > $x->bar(); > $x->barx(); > > package foo; > > sub new { > my $this = shift; > my $class = ref($this) || $this; Don't do this: http://www.stonehenge.com/merlyn/UnixReview/col52.html Just extract the $class. Now to answer your question. > my $self={}; > bless ($self, $class); > return $self; > } > > sub bar > { > my $self = shift; > print "foo\n"; > } > ################################# > > now, executing this code with "perl -cw script.pl" will not produce any > errors since the call for the reference of "barx" will only > be evaluated during runtime. > is there a way to detect such errors in compile time? First of all, you can sort of cheat and use ->can (see perldoc UNIVERSAL) or whatever in a BEGIN { ... } block, which -c runs. Otherwise, there cannot be a way because the class with which a variable is blessed to is not known at compile-time and may actually change in run-time: [code] my $x = OneClass->new(...); . . . if (int(rand(2)) == 0) { $x = CompletelyDifferentClass->new(...); } . . . $x->my_method();? # What now? [/code] So you need to rely on the run-time exception and your automated tests' suite to overcome this: https://docs.google.com/View?id=dcsvntt2_25wpjvbbhk (Strong Typing vs. Strong Testing). Regards, Shlomi Fish -- ----------------------------------------------------------------- Shlomi Fish http://www.shlomifish.org/ Optimising Code for Speed - http://shlom.in/optimise <rindolf> She's a hot chick. But she smokes. <go|dfish> She can smoke as long as she's smokin'. Please reply to list if it's a mailing list post - http://shlom.in/reply . _______________________________________________ Perl mailing list Perl@perl.org.il http://mail.perl.org.il/mailman/listinfo/perl
