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Re: Can function pointers be compared for equality

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On 2012-01-23, Ben Pfaff <blp@cs.stanford.edu> wrote:
> Malcolm McLean <malcolm.mclean5@btinternet.com> writes:
>
>> On Jan 23, 1:54 pm, "V.Subramanian, India"
>> <subramanian10...@yahoo.com> wrote:
>>>
>>> Is this equality comparison check of function pointers, legal, correct
>>> and allowed ? (Note that it works in my implementation of gcc. But I
>>> do not want to go by one particular implementation).
>>>
>>> Please explain.
>>>
>> You can compare function ponters for equality. However you can't
>> compare for inequality.  [...]
>
> In C, != is the inequality operator.  You can compare function
> pointers with !=.  You cannot compare them with the relational
> operators < > <= >=.

Fuck the C terminlogy and the insipid monkeys behind it, who long should have
called it quits.

In English math terminology, this is called an equation:

  3x + 4 = 7

and this is called an inequality:

  3x + 4 < 7

(Those of you who don't remember, ask the nearest fifth grader.)

A "relation" is a mapping between sets. Equality is a kind of relation
("equivalence relation") and so the == operator can rightfully be called
"relational".

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Can function pointers be compared for equality "V.Subramanian, India" <subramanian100in@yahoo.com> - 2012-01-23 05:54 -0800
  Re: Can function pointers be compared for equality Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-01-23 07:00 -0800
    Re: Can function pointers be compared for equality blp@cs.stanford.edu (Ben Pfaff) - 2012-01-23 07:46 -0800
      Re: Can function pointers be compared for equality Kaz Kylheku <kaz@kylheku.com> - 2012-01-23 20:06 +0000
        Re: Can function pointers be compared for equality ec429 <ec429@cam.ac.uk> - 2012-01-23 20:42 +0000
          Re: Can function pointers be compared for equality James Kuyper <jameskuyper@verizon.net> - 2012-01-23 16:04 -0500
            Re: Can function pointers be compared for equality Ian Collins <ian-news@hotmail.com> - 2012-01-24 10:24 +1300
              Re: Can function pointers be compared for equality James Kuyper <jameskuyper@verizon.net> - 2012-01-23 16:48 -0500
              Re: Can function pointers be compared for equality Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-24 03:04 -0800
                Re: Can function pointers be compared for equality gwowen <gwowen@gmail.com> - 2012-01-24 03:37 -0800
            Re: Can function pointers be compared for equality Kleuske <kleuske@nowhere.net> - 2012-01-23 21:39 +0000
            Re: Can function pointers be compared for equality gwowen <gwowen@gmail.com> - 2012-01-24 03:31 -0800
              Re: Can function pointers be compared for equality ec429 <ec429@cam.ac.uk> - 2012-01-24 13:16 +0000
          Re: Can function pointers be compared for equality Kaz Kylheku <kaz@kylheku.com> - 2012-01-23 22:11 +0000
            Re: Can function pointers be compared for equality Ian Collins <ian-news@hotmail.com> - 2012-01-24 11:34 +1300
    Re: Can function pointers be compared for equality Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-23 16:37 +0000
    Re: Can function pointers be compared for equality Keith Thompson <kst-u@mib.org> - 2012-01-23 09:11 -0800
      Re: Can function pointers be compared for equality pete <pfiland@mindspring.com> - 2012-01-23 20:06 -0500
        Re: Can function pointers be compared for equality Keith Thompson <kst-u@mib.org> - 2012-01-23 17:45 -0800
          Re: Can function pointers be compared for equality Kaz Kylheku <kaz@kylheku.com> - 2012-01-24 03:48 +0000
            Re: Can function pointers be compared for equality James Kuyper <jameskuyper@verizon.net> - 2012-01-23 22:59 -0500
              Re: Can function pointers be compared for equality Kaz Kylheku <kaz@kylheku.com> - 2012-01-24 04:22 +0000
                Re: Can function pointers be compared for equality Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-24 03:07 -0800
                Re: Can function pointers be compared for equality Kleuske <kleuske@nowhere.net> - 2012-01-24 11:16 +0000

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