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Re: Evaluation Order in Function Declaration

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On 2012-02-28, Jens Gustedt <jens.gustedt@loria.fr> wrote:
> Hello,
>
> Am 02/28/2012 06:22 AM, schrieb Shao Miller:
>> Is the evaluation order guaranteed to be left-to-right for the
>> declaration of 'baz' in the following code?  Or are the array size
>> expressions unsequenced relative to one another, as in 'a + b'?  Or
>> something else?
>> 
>>   #include <stdio.h>
>> 
>>   int foo(void) { puts("foo"); return 1; }
>>   int bar(void) { puts("bar"); return 1; }
>> 
>>   int baz(int (* x)[foo()], int (* y)[bar()]) { return 0; }
>> 
>>   int main(void) { return baz(0, 0); }
>
> Yes, not only that it is left to right, you are even allowed to use each
> of the preceding identifiers in the expressions. Otherwise things like
>
> double sum(size_t n, size_t m, double A[n][m]) { ... }
>
> could never work reliably.

Sure they could. The above could mean that A[n][m], n and m independently
receive values from the same sources (the argument expressions). The [n][m]
doesn't have to refer to the values stored in the parameters n, and m
but rather the [n][m] can indicate additional sinks for the data flows
emanating from argument 1 and 2.

Such semantics can be hammered out.  There is no end to how you can lay weasely
traps for the programmer (as the sordid history of this language shows.)

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Evaluation Order in Function Declaration Shao Miller <sha0.miller@gmail.com> - 2012-02-28 00:22 -0500
  Re: Evaluation Order in Function Declaration Jens Gustedt <jens.gustedt@loria.fr> - 2012-02-28 10:14 +0100
    Re: Evaluation Order in Function Declaration Kaz Kylheku <kaz@kylheku.com> - 2012-02-28 09:31 +0000
      Re: Evaluation Order in Function Declaration Jens Gustedt <jens.gustedt@loria.fr> - 2012-02-28 13:09 +0100
  Re: Evaluation Order in Function Declaration pete <pfiland@mindspring.com> - 2012-03-08 08:49 -0500

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