The type of stacks containing elements of type 'a.

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

Return a new stack, initially empty.

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

pop s removes and returns the topmost element in stack s, or

• raises Empty

  if the stack is empty.

top s returns the topmost element in stack s, or

• raises Empty

  if the stack is empty.

Discard all elements from a stack.

Return a copy of the given stack.

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

Return the number of elements in a stack.

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.

enum s returns an enumeration of the elements of stack s, from the most recently entered to the least recently entered. This enumeration is made on a copy of the input stack, and reading from it will not affect s.

enum_destruct s returns a destructive enumeration of the elements of stack s, from the most recently entered to the least recently entered. Reading the enumeration will progressively empty s.

of_enum e returns a new stack containing all the elements of e. This is equivalent to calling push with the first element of the enumeration, then with the second, etc.

Note: if s is a stack, s <> of_enum (enum s), as of_enum reverses the input order.