From: Takaaki Tateishi <ttate@...>
Date: 2005-10-18T04:12:17+09:00
Subject: Re: Ruby/DL union! method syntax

gregarican wrote:
> I read the Ruby/DL docs on using the struct! method and have an
> understanding about it. How about the union! method? I have googled
> around and can't find any examples of its use. The following test code
> doesn't seem to work:
> --------------------------
> require 'dl'
> thisStruct=DL.malloc(4)
> thisStruct.struct!('L', :longPointer)
> thatStruct=DL.malloc(2)
> thatStruct.struct!('H', :shortPointer)
> theUnion=DL.malloc(6)
> theUnion.union!(thisStruct, thatStruct)

You should pass a signature and labels like struct!.

theUnion.union!('LH', :long, :short)
theUnion[:long] = 2**16
p theUnion[:long]    # => 65536
p theUnion[:short]   # => 0
-- 
Takaaki Tateishi <ttate@ttsky.net>