std.typetuple
Templates with which to manipulate type tuples (also known as type lists). Some operations on type tuples are built in to the language, such as TL[n] which gets the nth type from the type tuple. TL[lwr .. upr] returns a new type list that is a slice of the old one. References:Based on ideas in Table 3.1 from Modern C++ Design, Andrei Alexandrescu (Addison-Wesley Professional, 2001)
- Creates a typetuple out of a sequence of zero or more types.
Example:
import std.typetuple; alias TypeTuple!(int, double) TL; int foo(TL td) // same as int foo(int, double); { return td[0] + cast(int)td[1]; }
Example:
TypeTuple!(TL, char) // is equivalent to: TypeTuple!(int, double, char)
- Returns the index of the first occurrence of type T in the
sequence of zero or more types TList.
If not found, -1 is returned.
Example:
import std.typetuple; import std.stdio; void foo() { writefln("The index of long is ", indexOf!(long, TypeTuple!(int, long, double))); // prints: The index of long is 1 }
- Kept for backwards compatibility
- Returns a typetuple created from TList with the first occurrence,
if any, of T removed.
Example:
Erase!(long, int, long, double, char) // is the same as: TypeTuple!(int, double, char)
- Returns a typetuple created from TList with the all occurrences,
if any, of T removed.
Example:
alias TypeTuple!(int, long, long, int) TL; EraseAll!(long, TL) // is the same as: TypeTuple!(int, int)
- Returns a typetuple created from TList with the all duplicate
types removed.
Example:
alias TypeTuple!(int, long, long, int, float) TL; NoDuplicates!(TL) // is the same as: TypeTuple!(int, long, float)
- Returns a typetuple created from TList with the first occurrence
of type T, if found, replaced with type U.
Example:
alias TypeTuple!(int, long, long, int, float) TL; Replace!(long, char, TL) // is the same as: TypeTuple!(int, char, long, int, float)
- Returns a typetuple created from TList with all occurrences
of type T, if found, replaced with type U.
Example:
alias TypeTuple!(int, long, long, int, float) TL; ReplaceAll!(long, char, TL) // is the same as: TypeTuple!(int, char, char, int, float)
- Returns a typetuple created from TList with the order reversed.
Example:
alias TypeTuple!(int, long, long, int, float) TL; Reverse!(TL) // is the same as: TypeTuple!(float, int, long, long, int)
- Returns the type from TList that is the most derived from type T.
If none are found, T is returned.
Example:
class A { } class B : A { } class C : B { } alias TypeTuple!(A, C, B) TL; MostDerived!(Object, TL) x; // x is declared as type C
- Returns the typetuple TList with the types sorted so that the most
derived types come first.
Example:
class A { } class B : A { } class C : B { } alias TypeTuple!(A, C, B) TL; DerivedToFront!(TL) // is the same as: TypeTuple!(C, B, A)