Variant

Type that can hold one of the types listed as its template parameters.

$(D_PSYMBOL Variant) is a type similar to $(D_KEYWORD union), but $(D_PSYMBOL Variant) keeps track of the actually used type and throws an assertion error when trying to access an invalid type at runtime.

template Variant (

Specs...

) if (

isTypeTuple!Specs &&

NoDuplicates!Specs.length == Specs.length

) {

union AlignedUnion(Args...);

template accessor(T, Union);

template accessorImpl(T, Union, size_t tag);

struct Variant;

}

Members

Structs

Variant struct Variant: Undocumented in source.

Templates

accessor template accessor(T, Union): Undocumented in source.
accessorImpl template accessorImpl(T, Union, size_t tag): Undocumented in source.

Unions

AlignedUnion union AlignedUnion(Args...): Undocumented in source.

Parameters

Specs: Types this $(D_SPYBMOL Variant) can hold.

Examples

Variant!(int, double) variant = 5;
assert(variant.peek!int);
assert(variant.get!int == 5);

variant = 5.4;
assert(!variant.peek!int);
assert(variant.get!double == 5.4);