Display the source code in std/traits.d from which this page was generated on github.

If you spot a problem with this page, click here to create a Bugzilla issue.

Quickly fork, edit online, and submit a pull request for this page. Requires a signed-in GitHub account. This works well for small changes. If you'd like to make larger changes you may want to consider using local clone.

Alias `std.traits.ParameterStorageClassTuple`

Get a tuple of the storage classes of a function's parameters.


						
				alias ParameterStorageClassTuple(alias func)
				 = AliasSeq!();

Parameters

Name	Description
func	function symbol or type of function, delegate, or pointer to function

Returns

A tuple of ParameterStorageClass bits

Example

alias STC = ParameterStorageClass; // shorten the enum name

void func(ref int ctx, out real result, in real param, void* ptr)
{
}
alias pstc = ParameterStorageClassTuple!func;
static assert(pstc.length == 4); // number of parameters
static assert(pstc[0] == STC.ref_);
static assert(pstc[1] == STC.out_);
version (none)
{
    // TODO: When the DMD PR (dlang/dmd#11474) gets merged,
    // remove the versioning and the second test
    static assert(pstc[2] == STC.in_);
    // This is the current behavior, before `in` is fixed to not be an alias
    static assert(pstc[2] == STC.scope_);
}
static assert(pstc[3] == STC.none);

Authors

Walter Bright, Tomasz Stachowiak (isExpressions), Andrei Alexandrescu, Shin Fujishiro, Robert Clipsham, David Nadlinger, Kenji Hara, Shoichi Kato

License

Boost License 1.0.