Re^2: Refactoring Perl 4 - Replace Temp with Query

I don't usually use temp variables for that, but that's the idea, if you mean something like:

sub base_price{
    my $self = shift;

    if ( not $self->{_base_price} ){
        $self->{_base_price}
            =  $self->{_quantity} * $self->{_item_price};
    }
    return $self->{_base_price};
}
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That's how I usually do result caching for methods. There are other options too, like Memoize, although I haven't tried any of the modules that do this.

perl -e 'split//,q{john hurl, pest caretaker}and(map{print @_[$_]}(joi
+n(q{},map{sprintf(qq{%010u},$_)}(2**2*307*4993,5*101*641*5261,7*59*79
+*36997,13*17*71*45131,3**2*67*89*167*181))=~/\d{2}/g));'
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Re^3: Refactoring Perl 4 - Replace Temp with Query by akho (Hermit) on Jul 27, 2007 at 18:45 UTC
Won't work if `$self->{_item_price}` changes. Of course abstracting such things away is the right way to go; but you still often need temp variables. So this refactoring technique should probably be promoted as "do what common sense tells you", not as "remove temp vars". Memoize is a good thing too, btw. Even better with Memoize::Attrs.	[reply] [d/l]
Re^4: Refactoring Perl 4 - Replace Temp with Query by agianni (Hermit) on Jul 30, 2007 at 12:48 UTC
Right, up till now, I haven't had to do anything but the simplest forms of Memoization, so my example would generally work for me. I find myself doing memoization most often when I'm doing database queries that I expect should return the same things for the duration of the process, i.e. if handling a Web request. Obviously the situation would be different if one were running a persistent process. `perl -e 'split//,q{john hurl, pest caretaker}and(map{print @_[$_]}(joi +n(q{},map{sprintf(qq{%010u},$_)}(2*23074993,51016415261,75979 +36997,13177145131,3*26789167*181))=~/\d{2}/g));'` [download]	[reply] [d/l]