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From: jrc@ukc.ac.uk (John)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Can you nest subroutines in C?
Message-ID: <1701@harrier.ukc.ac.uk>
Date: 30 Jun 89 13:59:48 GMT
References: <4501@crash.cts.com>
Reply-To: jrc@ukc.ac.uk (John)
Organization: Computing Lab, University of Kent at Canterbury, UK.
Lines: 19

In article <4501@crash.cts.com> wade@pnet01.cts.com (Wade Bickel) writes:
>.. I do not understand why C does not support Nested routines.  ..

I think it's because you need to maintain a display (or something like that)
to resolve references to variables in enclosing procedures. C has a lean and
mean close to the machine philosophy, which this would run counter to.

It also causes all kinds of horrible problems if you want to have pointers to
functions - if you save a pointer to a nested function in an array, then call
it much later on from another part of your program, what should those external
variable references resolve to? Should a pointer to function in fact be a
structure containing the entire context of the function at the time the
pointer was created? All very un C-like.

There are two issues here - nested funtions and allowing references to
parameters in enclosing functions. BCPL (:-) has nested functions, but not
references to enclosing scopes (a nicer compromise, IMHO)

John Cupitt