Stack¶

A Stack is a collection of any type in kOS. Stacks work according to Last-In first-out principle. It may be useful to contrast Stack with Queue to better understand how both structures work. You can read more about stacks on Wikipedia.

Using a stack¶

SET S TO STACK().
S:PUSH("alice").
S:PUSH("bob").

PRINT S:POP. // will print 'bob'
PRINT S:POP. // will print 'alice'

Structure¶

structure Stack¶

Members¶
Suffix	Type	Description
All suffixes of `Enumerable`		`Stack` objects are a type of `Enumerable`
`PUSH(item)`	None	add item to the top of the stack
`POP()`	any type	returns the item on top of the stack and removes it
`PEEK()`	any type	returns the item on top of the stack without removing it
`CLEAR()`	None	remove all elements
`COPY`	`Stack`	a new copy of this stack

Note

This type is serializable.

Stack:PUSH(item)¶

Parameters

item – (any type) item to be added

Adds the item to the top of the stack.

Stack:POP()¶: Returns the item on top of the stack and removes it.

Stack:PEEK()¶: Returns the item on top of the stack without removing it.

Stack:CLEAR()¶: Removes all elements from the stack.

Stack:COPY¶

Type: Stack
Access: Get only

Returns a new stack that contains the same thing as the old one.