Apple-2-SW/jsbasic
1
0
Fork 0
mirror of https://github.com/inexorabletash/jsbasic.git synced 2024-12-30 15:29:22 +00:00
Code Issues Projects Releases Wiki Activity
Applesoft BASIC in JavaScript
174 Commits 1 Branch 0 Tags 1.2 MiB
JavaScript 61.4%
CSS 23.3%
HTML 15.3%
94994cd90f
Go to file
Joshua Bell 94994cd90f Fix links. Fixes #43
2022-01-29 10:24:27 -08:00
cm
res Move some resource files to res/ 2016-02-05 20:42:40 -08:00
samples Unit Tests: Fix TEXT, add failing FOR case 2021-03-31 20:28:41 -07:00
tools
vfs
.gitignore
basic.js Fix initialization 2021-03-31 20:45:46 -07:00
bell.js Use WebAudio for beep, if available 2017-02-19 21:17:01 -08:00
bs.html Add script example 2013-12-08 15:56:19 -08:00
display.css Move some resource files to res/ 2016-02-05 20:42:40 -08:00
dos.js Avoid RegExp.$1 and friends 2016-10-13 22:17:30 -07:00
favicon.ico Updated favicon 2015-03-12 21:25:07 -07:00
hires.js Improve GR/HGR colors 2020-06-13 10:38:34 -07:00
index.html Fix links. Fixes #43 2022-01-29 10:24:27 -08:00
index.js Add softswitch reads for display modes 2020-05-29 21:55:32 -07:00
LICENSE.md Update font refs to https 2018-08-15 21:55:00 -07:00
lores.js Improve GR/HGR colors 2020-06-13 10:38:34 -07:00
printer.js Remove copyright/license from individual JS files 2013-08-21 23:07:46 -07:00
README.md Update README.md 2018-08-14 13:00:32 -07:00
reference.html Fix typo 2022-01-29 10:19:28 -08:00
script.js Add softswitch reads for display modes 2020-05-29 21:55:32 -07:00
script.md Update font refs to https 2018-08-15 21:55:00 -07:00
styles.css Update font refs to https 2018-08-15 21:55:00 -07:00
tty.js Focus on the screen when keyboard register is read 2021-03-31 20:06:14 -07:00

README.md

jsbasic - Applesoft BASIC in JavaScript

This is hosted for playing with at https://inexorabletash.github.io/jsbasic/

Notes & Known Issues

  • The BASIC program is compiled to JavaScript before execution. Syntax errors are therefore detected at compile-time rather than at run-time as on a traditional interpreter. For example, the following program would run without errors on an Apple since the erroneous second statement is never reached. 10 END : CHR$(PRINT)
  • Handling of BASIC code that does not match the canonical LIST output format may not behave as on an Apple:
    • Keyword parsing differs from Applesoft command line. For example FOR I = S TO P doesn't collapse into FOR I = STOP.
  • Limitations:
    • Floating point overflow is only detected on variable assignment.
    • Only a subset of DOS 3.3 and ProDOS useful for basic file I/O are implemented.
    • Only a small number of common PEEK, POKE and CALL locations are supported.
    • Commands that refer to assembly routines (&, USR() etc.), shape tables, and tape I/O are not implemented.
  • Commands that operate on the program itself (LIST, RUN, DEL, etc.) are not implemented.
  • A handful of extensions are made beyond Applesoft BASIC:
    • To improve readability, lines may start with : and continue the previously numbered line.
    • DEF FN can define string functions
    • == can be used as =
    • CHR$() values > 255 do interesting things
    • HSCRN(x, y) allows probing the hi-res screen
    • hexadecimal literals e.g. $C010 can be used as numbers