Commit Graph

7 Commits

Author SHA1 Message Date
Eremey Valetov
0743757029 Implement DEF SEG/PEEK/POKE, GET/PUT sprites, fix PRINT USING, update to v0.11.0 2026-03-01 13:07:28 -05:00
Eremey Valetov
3fa8c6f034 Implement EDIT statement and ON TIMER/ON KEY event trapping, update to v0.9.0
Add event-driven programming: ON TIMER(n) GOSUB with TIMER ON/OFF/STOP,
ON KEY(n) GOSUB with KEY(n) ON/OFF/STOP for F1-F10. Fix F-key escape
sequence parser (F9/F10 detection, push back consumed bytes on unmatched
sequences). Add EDIT statement for TUI line editing. Guard key trap
polling so keystrokes aren't consumed when no traps are configured.
2026-02-27 17:29:09 -05:00
Eremey Valetov
b5bb78a174 Replace magic numbers in stack bounds checks with named constants
Define MAX_FOR_DEPTH, MAX_GOSUB_DEPTH, MAX_WHILE_DEPTH in interp.h
and use them in all overflow checks in interp.c.
2026-02-22 13:35:39 -05:00
Eremey Valetov
da6b513b07 Add AUTO, RENUM, DELETE, COMMON; fix LIST range parsing
AUTO generates line numbers during interactive editing, RENUM
renumbers program lines and patches all GOTO/GOSUB/ON references,
DELETE removes line ranges. COMMON declares variables preserved
across CHAIN. Also fixed LIST/DELETE range parsing (was broken by
expression evaluator consuming the dash as subtraction).

Bump to v0.7.0, 53 tests.
2026-02-22 12:58:47 -05:00
Eremey Valetov
c2d73e9c24 Phase 3: file I/O, PRINT USING, SAVE/LOAD, MID$ assignment, graphics stubs
Add OPEN/CLOSE with both modern (OPEN "f" FOR OUTPUT AS #n) and compact
(OPEN "O",#n,"f") syntaxes. PRINT#, WRITE#, INPUT#, LINE INPUT# for
sequential file access. EOF() now returns real file status with peek-ahead.
LOC/LOF return approximate values.

PRINT USING with numeric (#, ., +, -, $$, **, ^^^^, comma grouping) and
string (!, &, \ \) format specifiers. Shared by PRINT USING and PRINT# USING.

SAVE (ASCII), LOAD (with ,R auto-run), and MERGE for program persistence.

MID$ assignment (MID$(var$, start [,len]) = expr) for in-place string
modification. Works with both scalar variables and array elements.

Graphics stubs for SCREEN, PSET, PRESET, LINE, CIRCLE, DRAW, PAINT,
VIEW, WINDOW, PALETTE - parse and discard arguments so graphics-heavy
programs don't crash.

SYSTEM and NEW/CLEAR now close all open files. Version bumped to 0.3.0.
22 tests pass (16 existing + 6 new).
2026-02-10 11:53:28 -05:00
Eremey Valetov
616259537a Phase 2: variables, arrays, program execution, and control flow
Add variable storage (scalar and array), program line storage with
RUN/LIST/NEW, and full control flow: FOR/NEXT, GOTO, GOSUB/RETURN,
IF/THEN/ELSE, WHILE/WEND, ON GOTO/GOSUB, DATA/READ/RESTORE.

New modules: interp.c (1445 lines - execution loop and statement
dispatcher), vars.c, arrays.c, input.c. Version bumped to 0.2.0.
16 test programs pass including Leibniz pi and prime sieve.
2026-02-10 11:16:58 -05:00
Eremey Valetov
d8e8375366 Phase 1: expression calculator with direct mode
GW-BASIC reimplementation in C11, using Microsoft's open-sourced 8088
assembly as the authoritative reference.

Tokenizer (CRUNCH/LIST), expression evaluator with operator precedence,
all math functions (SIN, COS, TAN, ATN, SQR, LOG, EXP, RND, etc.),
string functions (LEFT$, RIGHT$, MID$, CHR$, ASC, VAL, STR$, etc.),
PRINT statement with comma/semicolon zones, TAB(), SPC().

Handles integer/single/double types with correct promotion, D exponent
for double-precision literals, type suffixes (%, !, #), &H hex/&O octal
literals, MBF conversion routines, and GW-BASIC-compatible number
formatting.

Platform-independent via HAL vtable; POSIX backend included.
2026-02-10 10:25:08 -05:00