Module Stack

module Stack: sig .. end

Last-in first-out stacks.

This module implements stacks (LIFOs), with in-place modification.

type 'a t

The type of stacks containing elements of type 'a.

exception Empty

Raised when Stack.pop or Stack.top is applied to an empty stack.

val create : unit -> 'a t

Return a new stack, initially empty.

val push : 'a -> 'a t -> unit

push x s adds the element x at the top of stack s.

val pop : 'a t -> 'a

pop s removes and returns the topmost element in stack s, or raises Stack.Empty if the stack is empty.

val top : 'a t -> 'a

top s returns the topmost element in stack s, or raises Stack.Empty if the stack is empty.

val clear : 'a t -> unit

Discard all elements from a stack.

val copy : 'a t -> 'a t

Return a copy of the given stack.

val is_empty : 'a t -> bool

Return true if the given stack is empty, false otherwise.

val length : 'a t -> int

Return the number of elements in a stack. Time complexity O(1)

val iter : ('a -> unit) -> 'a t -> unit

iter f s applies f in turn to all elements of s, from the element at the top of the stack to the element at the bottom of the stack. The stack itself is unchanged.

val fold : ('b -> 'a -> 'b) -> 'b -> 'a t -> 'b

fold f accu s is (f (... (f (f accu x1) x2) ...) xn) where x1 is the top of the stack, x2 the second element, and xn the bottom element. The stack is unchanged.

Since 4.03

The present documentation is copyright Institut National de Recherche en Informatique et en Automatique (INRIA). A complete version can be obtained from this page.