Commit | Line | Data |
---|---|---|
08689895 HE |
1 | \ SAVE-INPUT and RESTORE-INPUT |
2 | ||
3 | anew task-save-input.fth | |
4 | ||
5 | private{ | |
6 | ||
7 | : save-buffer ( -- column source-id 2 ) >in @ source-id 2 ; | |
8 | ||
9 | : restore-column ( column -- flag ) | |
09d08b41 HE |
10 | source nip over < |
11 | IF drop true | |
12 | ELSE >in ! false | |
13 | THEN | |
08689895 HE |
14 | ; |
15 | ||
16 | \ Return the file-position of the beginning of the current line in | |
17 | \ file SOURCE-ID. Assume that the current line is stored in SOURCE | |
18 | \ and that the current file-position is at an end-of-line (or | |
19 | \ end-of-file). | |
20 | : line-start-position ( -- ud ) | |
09d08b41 HE |
21 | source-id file-position throw |
22 | \ unless at end-of-file, subtract newline | |
23 | source-id file-size throw 2over d= 0= IF 1 s>d d- THEN | |
24 | \ subtract line length | |
25 | source nip s>d d- | |
08689895 HE |
26 | ; |
27 | ||
28 | : save-file ( column line filepos:ud source-id 5 -- ) | |
09d08b41 HE |
29 | >in @ |
30 | source-line-number@ | |
31 | line-start-position | |
32 | source-id | |
33 | 5 | |
08689895 HE |
34 | ; |
35 | ||
36 | : restore-file ( column line filepos:ud -- flag ) | |
09d08b41 HE |
37 | source-id reposition-file IF 2drop true exit THEN |
38 | refill 0= IF 2drop true exit THEN | |
39 | source-line-number! | |
40 | restore-column | |
08689895 HE |
41 | ; |
42 | ||
43 | : ndrop ( n*x n -- ) 0 ?do drop loop ; | |
44 | ||
45 | }private | |
46 | ||
47 | \ Source Stack | |
48 | \ EVALUATE >IN SourceID=(-1) 2 | |
49 | \ keyboard >IN SourceID=(0) 2 | |
50 | \ file >IN lineNumber filePos SourceID=(fileID) 5 | |
51 | : SAVE-INPUT ( -- column {line filepos}? source-id n ) | |
09d08b41 HE |
52 | source-id case |
53 | -1 of save-buffer endof | |
54 | 0 of save-buffer endof | |
55 | drop save-file exit | |
56 | endcase | |
08689895 HE |
57 | ; |
58 | ||
59 | : RESTORE-INPUT ( column {line filepos}? source-id n -- flag ) | |
09d08b41 HE |
60 | over source-id <> IF ndrop true exit THEN |
61 | drop | |
62 | case | |
63 | -1 of restore-column endof | |
64 | 0 of restore-column endof | |
65 | drop restore-file exit | |
66 | endcase | |
08689895 HE |
67 | ; |
68 | ||
69 | privatize |