Parallel Merge Sort

H. S. Teoh via Digitalmars-d digitalmars-d at
Tue Mar 3 21:55:04 PST 2015

On Wed, Mar 04, 2015 at 02:05:45AM +0000, anonymous via Digitalmars-d wrote:
> On Wednesday, 4 March 2015 at 01:17:00 UTC, H. S. Teoh wrote:
> >The 'in' modifier is the same as 'const' when applied to function
> >parameters, but writing 'in' documents that the parameters are input
> >parameters that won't be modified by the function.
> You forgot to mention "scope". "in" is short for "scope const".
> 'scope' means that the argument is used only in this run of the
> function; it's not stored anywhere (a global, a struct/class member,
> ...).

Ah, you're right, I forgot about that.

> >(Conversely, writing 'out' documents that the parameter is an output
> >parameter: the compiler initializes it to its default state, and the
> >function (presumably) stores its output value(s) in that parameter
> >before returning.  Semantically, 'out' is the same as mutable, which
> >is unmarked in D. But writing 'out' helps code maintainability by
> >documenting the intent of function parameters, so that readers of
> >your code don't have to guess what the purpose of the parameter might
> >be and how it should be used.)
> You forgot to mention that "out" parameters work like "ref" parameters
> (plus resetting to default value). That is, arguments are passed by
> reference; changes that the function makes affect the given lvalue at
> the call site.

Right again. I really need to check what I write before posting... :-(

Thanks for the corrections!


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