visit

Dispatches the value contained on a TaggedUnion or TaggedAlgebraic to a set of visitors.

A visitor can have one of three forms:

function or delegate taking a single typed parameter
function or delegate taking no parameters
function or delegate template taking any single parameter

....

auto visit(TU tu)
template visit(VISITORS...)
auto
visit
(
TU
)
(
auto ref TU tu
)
if (
isInstanceOf!(TaggedUnion, TU)
)
if (
VISITORS.length > 0
)
auto visit(TaggedAlgebraic!U ta)

Members

Functions

visit auto visit(TU tu): Undocumented in source. Be warned that the author may not have intended to support it.
visit auto visit(TaggedAlgebraic!U ta): Undocumented in source. Be warned that the author may not have intended to support it.

Examples

static if (__VERSION__ >= 2081) {
	import std.conv : to;

	union U {
		int number;
		string text;
	}
	alias TU = TaggedUnion!U;

	auto tu = TU.number(42);
	tu.visit!(
		(int n) { assert(n == 42); },
		(string s) { assert(false); }
	);

	assert(tu.visit!((v) => to!int(v)) == 42);

	tu.setText("43");

	assert(tu.visit!((v) => to!int(v)) == 43);
}

Meta

Source

See Implementation

taggedalgebraic visit templates