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in reply to Re: Self creating OO Module field accessors...
in thread Self creating OO Module field accessors...

What you also can do is:

for my $prop (qw [field1 field2 field3]) { eval sprintf <<'END', ($prop) x 3; sub %s { my $self = shift; if (@_) {$self->{%s} = shift}; return $self->{%s}; } } END }

I used to generate accessors in this way, in part because I felt that glob manipulation was scary and turning off strictness, however temporarily, was fragile. Tom Christiansen eventually managed to convince me that the eval approach is bad - firstly it is wasteful of memory (and processor) because each method is recompiled afresh; secondly because it is deferred, and so a perl -c check won't show problems.

So these days I do it more like this:

for my $method (qw/ field1 field2 field3 /) { no strict 'refs'; *$method = sub { use strict 'refs'; my $self = shift; if (@_) {$self->{$method} = shift}; return $self->{$method}; }; }

Rather than creating 3 independent blocks of code, this creates 3 closures over the same block of code; in practice the resulting methods are otherwise identical. I also feel they are much easier to read this way, which is another aid for debugging and maintenance.

(I saw an alternative approach to the strictness here recently:

for my $method (qw/ ... /) { my $sub = sub { the code ... }; no strict 'refs'; *$method = $sub; }
.. which is probably better, but I haven't started using it yet.)

See Re: Things I Don't Use in Perl for some other things my autogenerated methods do.

Hugo