furo-forth-stack #
@furo/util v2.1.19
import '@furo/util/src/furo-forth-stack.js';
exports FuroForthStack js
exports <furo-forth-stack> custom-element-definition
superclass LitElement
summary forth like stack
furo-forth-stack is a declarative stack, inspired by the forth stack.
https://hackaday.com/2017/01/27/forth-the-hackers-language/ http://wiki.laptop.org/go/Forth_stack_operators http://galileo.phys.virginia.edu/classes/551.jvn.fall01/primer.htm#stacks
Attributes and Properties #
size #
default: 0
Current size of the stack
Events #
stack-size-changed #
at-stack-size-changed
→ Number
Fired when the stack size changes with Integer with the current size of the stack.
rotated #
at-rotated
→ the top element
Fired when stack was rotated
stack-changed #
at-stack-changed
→ the top element
Fired when the stack contents changes after put, drop,…
swapped #
at-swapped
→ void
Fired when stack was swapped
empty #
at-empty
→ void
Fired when stack gets empty
Methods #
clearStack #
clearStack() ⟹ void
* →
fn-clear-stack
Empties the stack and set the stack-size to 0
put #
put(e `` ) ⟹ void
`` → fn-put
Add an element to the stack
- e
swap #
swap() ⟹ void
* →
fn-swap
swap ( n1 n2 – n2 n1 )
swap, as you may have guessed, swaps the top two elements of the stack. For example:
1 2 3 4 swap will give you:
1 2 4 3 <- Top
drop #
drop() ⟹ void
* →
fn-drop
drop ( n – )
drop simply drops the top element of the stack. Running:
1 2 3 drop gives you a stack of:
1 2 <- Top
dup #
dup() ⟹ void
* →
fn-dup
dup ( n – n n )
dup is short for “duplicate” – it duplicates the top element of the stack. For example, try this out:
1 2 3 dup
You should end up with the following stack:
1 2 3 3 <- Top
over #
over() ⟹ void
* →
fn-over
over ( n1 n2 – n1 n2 n1 )
over is a bit less obvious: it takes the second element from the top of the stack and duplicates it to the top of the stack. Running this:
1 2 3 over will result in this:
1 2 3 2 <- Top
rot #
rot() ⟹ void
* →
fn-rot
rot ( n1 n2 n3 – n2 n3 n1 )
Finally, rot “rotates” the top three elements of the stack. The third element from the top of the stack gets moved to the top of the stack, pushing the other two elements down.
1 2 3 rot gives you:
2 3 1 <- Top
rrot #
rrot() ⟹ void
* →
fn-rrot
rrot ( n1 n2 n3 – n3 n1 n2 )
Reverse rotation or right rotation rrot “rotates” the elements of the stack inverse to rot. The top elemen the stack gets moved to the bottom of the stack.
1 2 3 rot gives you:
3 1 2 <- Top