[Development] RFC: lambda or lambda return from lambda?

[Marc Mutz]

On Monday 01 February 2016 10:18:25 Jędrzej Nowacki wrote:
> So it would look like that:
> 
>   fields.erase(std::remove_if(fields.begin(), 
>                               fields.end(),
>                               [&name](const QPair<QByteArray, QByteArray> 
> &header)
>                                   {
>                                       return qstricmp(name.constData(), 
> header.first) == 0;
>                                   }),
>                fields.end());
> 
> // I hope that formating is still ok, and the code is not wrapped.
> 

I am a great fanboy of algorithms and the STL, as should be clear by now :)

But I find the inlined lambda worse than an explicit loop. This is write-only 
code, imo. Esp. since we can't (yet) use auto in the parameter list, but even 
then, I'd always give a lambda a name (cf. my mail in response to Christian).

> For a bigger code we would actually require named functions. What do you 
> think?

Named functions have two problems: a) that many compilers don't inline the 
code. So at a minimum, you'd write a forwarding lambda, or the function would 
be an auto variable holding a stateless lambda (the difference between the two 
is almost non-existent, anyway). And b) that they cannot carry state. Lambdas 
can.

Thanks,
Marc

-- 
Marc Mutz <marc.mutz at kdab.com> | Senior Software Engineer
KDAB (Deutschland) GmbH & Co.KG, a KDAB Group Company
Tel: +49-30-521325470
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