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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Recursion, Yo
Date: Tue, 09 Apr 2024 13:31:32 -0700
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Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
> On 09.04.2024 16:27, Ben Bacarisse wrote:
>> Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
>>>
>>>   func ___(_) { return __(_,x^x,x^x^x) }
>>>   func __(_,_x,x_) { return --_?__(_,x_,_x+x_):_x+x_ }
>> 
>> The trouble with AWK (without gawk's -M) is that functions like this
>> just start to give a wrong, but plausibly sized, result.  For example
>> ___(80) is 23416728348467684 when it should be 23416728348467685.
>
> A general issue with functions and arithmetic producing "too large"
> numbers with languages and systems that don't support them. Yes.
>
> I'd prefer at least an error indication, though, and not a silent
> overflow.

If I understand correctly, it's not overflow, it's quiet loss of
precision.

awk doesn't normally distinguish between integer and floating-point
numbers, and uses FP to represent integers.  A computation that should
yield 23416728348467685 doesn't overflow, but it quietly yields
23416728348467684.  (`gawk -M` supports arbitrary precision integer
arithmetic.)

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */