val lexicographic : ('a->'a-> int) list->'a->'a-> int
lexicographic cmps x y compares x and y lexicographically using functions in the list cmps.
val lift :
('a->'a->'int_or_bool)->f:('b->'a)->'b->'b->'int_or_bool
lift cmp ~f x y compares x and y by comparing f x and f y via cmp.
moduleInherit (C : sig ... end) (T : sig ... end) : Swithtypet := T.t
Inherit comparability from a component.
Usage example:
module Foo = struct
module T = struct
type t = ... [@@deriving_inline compare, sexp][@@@end]
end
include T
include Comparable.Make (T)
end
Then include Comparable.S in the signature (see comparable_intf.mli for an example).
To add an Infix submodule:
module C = Comparable.Make (T)
include C
module Infix = (C : Comparable.Infix with type t := t)
Common pattern: Define a module O with a restricted signature. It aims to be (locally) opened to bring useful operators into scope without shadowing unexpected variable names. E.g. in the Date module:
module O = struct
include (C : Comparable.Infix with type t := t)
let to_string t = ..
end
Opening Date would shadow now, but opening Date.O doesn't:
let now = .. in
let someday = .. in
Date.O.(now > someday)