package containers

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Equality Combinators

  • since 1.2
type 'a t = 'a -> 'a -> bool

Equality function. Must be transitive, symmetric, and reflexive.

val poly : 'a t

Standard polymorphic equality.

val physical : 'a t

Standard physical equality.

  • since 2.0
val int : int t
val string : string t
val bool : bool t
val float : float t
val unit : unit t
val list : 'a t -> 'a list t
val array : 'a t -> 'a array t
val option : 'a t -> 'a option t
val pair : 'a t -> 'b t -> ('a * 'b) t
val triple : 'a t -> 'b t -> 'c t -> ('a * 'b * 'c) t
val map : ('a -> 'b) -> 'b t -> 'a t

map f eq is the equality function that, given objects x and y, projects x and y using f (e.g. using a record field) and then compares those projections with eq. Example: map fst int compares values of type (int * 'a) by their first component.

val always_eq : _ t

Always returns true. All values are equal.

  • since 3.0
val never_eq : _ t

Always returns false. No values are, so this is not even reflexive (i.e. x=x is false). Be careful!

  • since 3.0
module Infix : sig ... end
include module type of Infix
val (>|=) : 'b t -> ('a -> 'b) -> 'a t

Infix equivalent of map.