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Text File | 1993-09-24 | 990 b | 27 lines | [TEXT/MPS ] |
- (* Stacks *)
-
- (* This module implements stacks (LIFOs), with in-place modification. *)
-
- type 'a t mutable;;
- (* The type of stacks containing elements of type ['a]. *)
-
- exception Empty;;
- (* Raised when [pop] is applied to an empty stack. *)
-
- value new: unit -> 'a t
- (* Return a new stack, initially empty. *)
- and push: 'a -> 'a t -> unit
- (* [push x s] adds the element [x] at the top of stack [s]. *)
- and pop: 'a t -> 'a
- (* [pop s] removes and returns the topmost element in stack [s],
- or raises [Empty] if the stack is empty. *)
- and clear : 'a t -> unit
- (* Discard all elements from a stack. *)
- and length: 'a t -> int
- (* Return the number of elements in a stack. *)
- and iter: ('a -> 'b) -> '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. *)
- ;;
-