[fpc-devel] Optimizing unused return values of inline functions

[Thaddy de Koning]

> On 21.08.2017 13:22, Michael Van Canneyt wrote:
>>
>>
>> On Mon, 21 Aug 2017, Benito van der Zander wrote:
>>
>>> Hi,
>>>
>>>> This pattern is not inherently efficient. Why should it be ?
>>>
>>>
>>> It is not efficient, because of the pointless instruction!
>>
>> I am not speaking of the current FPC implementation. It may well be that
>> the
>> code is not most optimal.
>>
>> I am asking, why do you think *this pattern* (of always returning self)
>> should be inherently more efficient ?
>
> The pattern definitely has its uses. E.g. in the user space of our
> operating system at work we have a StdOutPrinter class that is used like
> this:
>
> === code begin ===
>
> StdIO::stdOutPrinter()->out("Helllo World ")->out(42)->out("
> ")->hex()->out(42)->line();
>
> === code end ===
>
> Each function returns again the instance that was returned by
> StdIO::stdOutPrinter().
>
> The whole pattern is called method chaining or fluent interface:
> - https://en.wikipedia.org/wiki/Method_chaining
> - https://en.wikipedia.org/wiki/Fluent_interface
>
> Regards,
> Sven
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>
E.g. KOL is based on this (or very close). The core methods always return
self.