From: Thomas Hafner <thomas@...>
Date: 2009-05-04T23:40:05+09:00
Subject: Re: lazy lookup

Robert Klemme <shortcutter@googlemail.com> wrote/schrieb <763388F1amqkuU1@mid.individual.net>:

> Sorry to sound discouraging but there is memoize already. The
> difference is that not the whole Hash is filled but only the one
> that you need for the argument list provided which seems potentially
> more efficient.

In my situation this ist not the case. The key value pairs can be
retrieved by reading a file. It's better to open/read/close the file
only once and retrieve all key value pairs at the same time. Of course
the file should not be read at all, if never a value will be
requested.

> In case you want to fill the Hash completely you can just replace the
> calculation code to assign multiple values.

How does that look like? Somethink like that?:

  Hash.new{ |h,k| h.replace(
      COMPLETELY_CALCULATED_HASH
    ); h[k] }

(COMPLETELY_CALCULATED_HASH should be replaced by some code which
calculates the hash completely)

Regards
  Thomas