Path: utzoo!attcan!uunet!lll-winken!ames!ncar!boulder!sunybcs!rutgers!mit-eddie!uw-beaver!uw-june!pardo
From: pardo@june.cs.washington.edu (David Keppel)
Newsgroups: comp.lang.misc
Subject: Re: The paradigm of Icon
Summary: Smalltalk isn't "procedural".
Message-ID: <6902@june.cs.washington.edu>
Date: 9 Jan 89 20:22:51 GMT
References: <8611@megaron.arizona.edu>
Reply-To: pardo@cs.washington.edu (David Keppel)
Organization: U of Washington, Computer Science, Seattle
Lines: 30

>In article  <2630@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>>[define "procedural language": all modules have parent-child
>> relationship]
>>[Smalltalk uses messages, but generally have parent-child
>> relationship => procedures]

gudeman@arizona.edu (David Gudeman) writes:
>[I suspect Smalltalk is implemented with procedure calls]

A common piece of Smalltalk is

    method1
	(boolVar) ifTrue: [block]

The ``calling'' sequence is as follows:

	Method1 is invoked.  This allocates call frame f1.
	The method "ifTrue:" is called with parameter "block".
		This allocates call frame f2.
	If the reciever "boolVar" is the value "True", then the
		argument "block" is executed IN CALL FRAME F1.

Thus, the block argument (closure) is executed in the environment of
some parent and this is *not* a parent-child calling order.  Of course
parent-child ordering *can* happen, it just isn't such a general case.

	;-D on  ( My own silly opinion )  Pardo
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