tinybasic.rkt

TinyBASIC implementation. Great language to practice with Racket's lex/yacc clone.

More information

• http://www.ittybittycomputers.com/IttyBitty/TinyBasic/TBuserMan.htm
• https://en.wikipedia.org/wiki/Tiny_BASIC

Installation

raco pkg install tinybasic

Usage

Run tinybasic or racket -l tinybasic to start the tinybasic monitor. To run a program and quit, try tinybasic --batch yourprogram.bas. Drop the --batch if you wish to load the program then start the tinybasic monitor.

Alternately, you may also use Racket's #lang facility:

#lang tinybasic
100 PRINT "Hello, world!"
120 END

(Run this via racket your-hashlang-tinybasic-file.bas.)

Status

It mostly works.

TODO

• INPUT should prompt with ? if output line is empty
• racket -l tinybasic/examples/fizzbuzz --repl should open a tinybasic monitor (I think this should also fix DrRacket interaction.)

Differences

New statement - BYE

Exit TinyBasic monitor.

Example:

REM Exits tinybasic.rkt and returns control back to shell.
BYE

New statement - LOAD

Load a line-numbered program from a file. Direct-mode lines (ones without a line number) are ignored.

Example:

REM Loads examples/hello.bas.
LOAD "examples/hello.bas"

New statement SAVE

Save a program to a file.

Example:

REM Saves hello.bas
10 PRINT "Hello, world!"
SAVE "examples/hello.bas"

New statement RACKET

Run Racket code with access to the interpreter's variables.

This escape hatch gives the user a way to call native Racket code. This means you could in theory write useful, modern applications in tinybasic. Pretty cool eh?

10 REM Greet the user
20 RACKET (printf "Hello, ~a.  How are you today?\n" (or (getenv "USER") (getenv "USERNAME")))
30 END

If the user set!'s a single upper case variable, it will copy over to the Tinybasic environment. Otherwise, if the user set!'s a single lower case variable, it will copy over. Otherwise the original value is copied over (default is 0).

Contrib

There are examples in the tinybasic-examples package. If you use org-mode, one can use ob-basic.el contained in the tinybasic-examples package to evaluate tinybasic programs in org-mode src blocks.

License

tinybasic.rkt is covered under MIT/X.

Files in examples/nonfree/ and TBuserMan.txt are of unknown license - consider all rights reserved.