Maentwrog is an RPN-calculator-turned-FORTH-interpreter which probably counts as Chris Pressey's first proper programming language. It was implemented on his Amiga 500 in 1993, then lost and unearthed multiple times. It is hardly remarkable, save that it spawned Befunge-93.
Sample Program
*a *b *c
0 =a 1 =b
: fib a b + =c c . b =a c =b c 100000 < @fib ;
1 . fib
Computational Class
Programming Paradigms
Documentation
Implementations
Download
Development
Github: catseye/Maentwrog
Bitbucket: catseye/maentwrog
Issue tracker: on github
Previous Releases
Influenced
Commentary
There are no extant example programs from the time the language was first
implemented — I tried writing the Sieve of Eratosthenes in it once,
but never got it to work, probably because == was not
implemented correctly. Recently, example programs and a description of the
language (which has become the provisional spec) have been provided by
Marinus — thanks Marinus!
Maentwrog is the name of a town in Wales, but the usage of its name for this language came via Douglas Adams' "The Meaning of Liff", wherein it is defined thusly: "MAENTWROG (n. Welsh) Celtic word for a computer spelling mistake."