A less approximate version of Tie::Hash::Approx

[Adam Bernard]

On 13/03/2008, Zbigniew Lukasiak <zzbbyy at gmail.com> wrote:
> On Wed, Mar 12, 2008 at 3:50 PM, David Cantrell <david at cantrell.org.uk> wrote:
>  > I need a module that will let me tie a hash so that if I try to FETCH a
>  >  value for a key that exists, then it'll return the appropriate value,
>  >  but will also let me fetch values for keys that match certain rules.
>  >
>  >  eg so that ...
>  >
>  >     tie %hash, ....
>  >     $hash{Hobbes} = 'feline';
>  >     $hash{Lassie} = 'canine';
>  >     # set up some magic here
>  >
>  >     print "Hobbes is a $hash{Hobbes}\n";
>  >     print "Lassie is a $hash{Lassie}\n";
>  >     print "42 is an $hash{42}\n";        # 42 gets caught by some magic
>  >     print "3.5 is a $hash{3.5}\n";       # 3.5 matches some other magic
>  >     print "Skippy is a $hash{Skippy}\n"; # Skippy doesn't exist
>  >
>  >  will print:
>  >
>  >     Hobbes is a feline
>  >     Lassie is a canine
>  >     42 is an integer
>  >     3.5 is a floating point number
>  >     Skippy is a Use of uninitialized value in concatenation
>  >
>  >  without me having to define values for all real numbers, which would be
>  >  the sort of task I might set a work-experience kid if I don't like their
>  >  haircut.
>  >
>  >  Can anyone point me at something on the CPAN, or am I going to have to
>  >  write this myself?
>  >
>
>
> Maybe not very helpful - but I think it is hard to see where you would
>  like to stop your generalisation before getting a universal function
>  call instead of a hash lookup.

I know of no module that does this already, but perhaps one could do
it by using regexes and/or code blocks as hash keys - if a searched
key wasn't present among the normal values (possibly including the
stringified forms of references), you could fall back to checking it
against those expressions?

Adam