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From: bouma@cs.purdue.EDU (William J. Bouma)
Newsgroups: comp.lang.forth
Subject: Re: ... and zen there were objects.
Message-ID: <11376@medusa.cs.purdue.edu>
Date: 15 Aug 90 22:49:10 GMT
Organization: Department of Computer Science, Purdue University
Lines: 46

In article <1498.UUL1.3#5129@willett.pgh.pa.us> dwp@willett.pgh.pa.us (Doug Philips) writes:
>I also dislike the necessity of doing message sends from the "inside
>out":
>	PushArg PushArg Object Message
>
>I say "inside out" because in traditional OO systems, say SmallTalk, the
>syntax is:
>	Object Message Arg Arg ...
>
>so the "inside out" syntax is neither "prefix" nor "post fix" but inside out.


    Well, you asked for feedback. I would say you are being needlessly
    picky here. Since when has anyone who advocates forth cared what any
    'traditional' language looks like. I would say the syntax with the
    message at the end is really the most forth-like. The function usually
    comes at the end in forth. The message is basically just an indirect
    function call.

	
>The SmallTalk syntax works nicely for both nesting and cascading.  Since
>Forth is post-fix, I think that the syntax should be:
>	PushArg PushArg Message Object


    Dissagree. I would call this syntax "inside out".
 

>That looks ok, but it does not do anything.  In order to do something you
>would have to add a special word.  I would pick SEND, as in:
>	10 20 MoveTo MyRectangle SEND


    SEND is a good word. But it should only be necessary if there is a
    message sitting on the stack. ie "normal" generic function call should
    go like this:
			PushArg PushArg Object Message

    But the same thing could be accomplished by:

			PushArg PushArg Object ' Message SEND

    Thus you can have messages returned on the stack and you can tell at
    a glance whether that is in fact what a line of code will do.
-- 
Bill <bouma@cs.purdue.edu>      Just ask the Axis   He knows everything