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From: eppstein@garfield.columbia.edu (David Eppstein)
Newsgroups: comp.lang.c++
Subject: "recursive" function prototype?
Message-ID: <5632@columbia.edu>
Date: 11 May 88 21:08:28 GMT
References: <2549@phoenix.Princeton.EDU> <461@goofy.megatest.UUCP> <7104@bellcore.bellcore.com> <11374@mimsy.UUCP>
Sender: nobody@columbia.edu
Organization: Columbia University CS Department
Lines: 20

sjs@spectral.ctt.bellcore.com (Stan Switzer):
> The lack of functions returning {functions returning}* can hardly be
> considered a serious flaw in C, but such functions ARE useful.

chris@mimsy.UUCP (Chris Torek):
> Agreed.  Traditionally, this has been done with ... [icky casts -- DE].

A cleaner approach is to wrap the function pointers in a recursive struct:

    struct foo;
    typedef foo (* foo_func)();
    struct foo {
	foo_func fn_ptr;
	foo(foo_func f) { fn_ptr = f; }
	foo operator()() { return (*fn_ptr)(); }
    };

    foo bar() { return bar; }
-- 
David Eppstein   eppstein@garfield.columbia.edu   Columbia U. Computer Science