Commit Graph

5 Commits

Author SHA1 Message Date
Virgil Dupras
6757c097ea forth: change the whole execution model again
Things are better now, but immediates inside colons are broken. However,
IF/THEN/ELSE are now immediates and it's much cleaner this way. Still, this
commit has too much stuff in it, I need to commit, I don't want to lose this
step.
2020-03-10 21:37:06 -04:00
Virgil Dupras
03e529b762 forth: simplify execution model and handle literals better
This scheme of "when we handle line-by-line, compile one word at a time then
execute" so that we could allow words like "CREATE" to call "readword" before
continuing was a bad scheme. It made things like branching outside of a colon
definition impossible.

This commit implement a new "litWord". When an undefined word is encountered at
compile time, it is included as-is in a string literal word. It is at run time
that we decide what to do with it.
2020-03-09 14:14:26 -04:00
Virgil Dupras
989d8bbabf forth: add "DOES>" and "CONSTANT" 2020-03-07 22:18:14 -05:00
Virgil Dupras
f0cf10ab7c forth: Check for PS underflow 2020-03-07 20:20:11 -05:00
Virgil Dupras
49228e418c apps/forth: new (WIP) application 2020-03-07 12:13:15 -05:00