Module Core_kernel__.Comparator
Extends Base.Comparator
, providing a type-indexed value that allows you to compare values of that type.
type ('a, 'witness) t
= private ('a , 'witness ) Base.Comparator.t
=
{
}
include module type of Base.Comparator with type ('a, 'witness) Comparator .t := ('a , 'witness ) t
A type-indexed value that allows one to compare (and for generating error messages, serialize) values of the type in question.
One of the type parameters is a phantom parameter used to distinguish comparators potentially built on different comparison functions. In particular, we want to distinguish those using polymorphic compare from those using a monomorphic compare.
type ('a, 'witness) t
= private
{
compare : 'a -> 'a -> int;
sexp_of_t : 'a -> Base.Sexp.t ;
}
type ('a, 'b) comparator
= ('a , 'b ) t
module type S = sig ... end
module type S1 = sig ... end
module type S_fc = sig ... end
val make : compare:('a -> 'a -> int) -> sexp_of_t:('a -> Base.Sexp.t ) -> (module S_fc with type comparable_t = 'a )
make
creates a comparator witness for the given comparison. It is intended as a lightweight alternative to the functors below, to be used like so: include (val Comparator.make ~compare ~sexp_of_t)
module Make = Base.Comparator.Make
Make
creates a comparator
value and its phantom comparator_witness
type for a nullary type.
module Make1 = Base.Comparator.Make1
Make1
creates a comparator
value and its phantom comparator_witness
type for a unary type. It takes a compare
and sexp_of_t
that have non-standard types because the Comparator.t
type doesn't allow passing in additional values for the type argument.
module Derived = Base.Comparator.Derived
Derived
creates a comparator
function that constructs a comparator for the type 'a t
given a comparator for the type 'a
.
module Derived2 = Base.Comparator.Derived2
Derived2
creates a comparator
function that constructs a comparator for the type ('a, 'b) t
given comparators for the type 'a
and 'b
.
module Derived_phantom = Base.Comparator.Derived_phantom
Derived_phantom
creates a comparator
function that constructs a comparator for the type ('a, 'b) t
given a comparator for the type 'a
.