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From: jlg@lambda.UUCP (Jim Giles)
Newsgroups: comp.lang.misc
Subject: GOTO vs. pointer vs. assignment (was Re: Relationship between C and C++)
Message-ID: <14290@lambda.UUCP>
Date: 23 Mar 90 21:41:44 GMT
References: <5200059@m.cs.uiuc.edu>
Lines: 30

From article <5200059@m.cs.uiuc.edu>, by robison@m.cs.uiuc.edu:
> [...]
> I think a closer analogy is the following:
> 
> 	Control flow		Data flow
> 	------------		---------
> 	label			r-value
> 	goto			assignment

Actually, this analysis is correct.  But, the original analogy was
also correct.  In the domain of data _structuring_ the element corres-
ponding to GOTO is the pointer.  In the domain of data _flow_ the
analogous element is the assignment.

> [...]                                   This would lead one to 
> conclude that any imperative language is "dangerous", whether 
> it has pointers or not.  

It not only _would_ lead to such a conclusion - it has (past tense).
What do you think all the functional language advocates are on
about?  Indeed, there is a sense in which assignment leads to 
some very complicated semantic issues which are completely avoided
in functional languages.  Fortunately for most of us, people tend
to have an intuitive understanding of these semantic problems that
makes concern about them somewhat less important.  The same goes
for GOTO (at least to some extent).  In my opinion, the problem
is worst for pointers than for either of the other two (people
_don't_ seem to understand pointers - intuitively or otherwise).

J. Giles