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.
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.
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).
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.
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.