blob: 0f7e097bff2771bcbf3e640687533122686beecc (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
\ *****************************************************************************
\ * Copyright (c) 2004, 2008 IBM Corporation
\ * All rights reserved.
\ * This program and the accompanying materials
\ * are made available under the terms of the BSD License
\ * which accompanies this distribution, and is available at
\ * http://www.opensource.org/licenses/bsd-license.php
\ *
\ * Contributors:
\ * IBM Corporation - initial implementation
\ ****************************************************************************/
\ Example:
\
\ To get a 30 element stack, go:
\
\ 0 > 30 new-stack my-stack
\ 0 > my-stack
\ 0 > 20 push 30 push
\ 0 > pop pop .s
0 value current-stack
: new-stack ( cells <>name -- )
create >r here ( here R: cells )
dup r@ 2 + cells ( here here bytes R: cells )
dup allot erase ( here R: cells)
cell+ r> ( here+1cell cells )
swap ! ( )
DOES> to current-stack
;
: reset-stack ( -- )
0 current-stack !
;
: stack-depth ( -- depth )
current-stack @
;
: push ( value -- )
current-stack @
current-stack cell+ @ over <= ABORT" Stack overflow"
cells
1 current-stack +!
current-stack 2 cells + + !
;
: pop ( -- value )
current-stack @ 0= ABORT" Stack underflow"
current-stack @ cells
current-stack + cell+ @
-1 current-stack +!
;
|
