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Alias `std.traits.CopyConstness`

Returns the type of Target with the "constness" of Source. A type's constness refers to whether it is const, immutable, or inout. If source has no constness, the returned type will be the same as Target.


						
				alias CopyConstness(FromType, ToType)
				 = Unshared!(CopyTypeQualifiers!(FromType,ToType));

Example

const(int) i;
CopyConstness!(typeof(i), float) f;
assert( is(typeof(f) == const float));

CopyConstness!(char, uint) u;
assert( is(typeof(u) == uint));

//The 'shared' qualifier will not be copied
assert(!is(CopyConstness!(shared bool, int) == shared int));

//But the constness will be
assert( is(CopyConstness!(shared const real, double) == const double));

//Careful, const(int)[] is a mutable array of const(int)
alias MutT = CopyConstness!(const(int)[], int);
assert(!is(MutT == const(int)));

//Okay, const(int[]) applies to array and contained ints
alias CstT = CopyConstness!(const(int[]), int);
assert( is(CstT == const(int)));

Authors

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

License

Boost License 1.0.