SixtyPical/README.markdown

SixtyPical

SixtyPical is a very low-level programming language, similar to 6502 assembly, with static analysis through abstract interpretation.

In practice, this means it catches things like

• you forgot to clear carry before adding something to the accumulator
• a subroutine that you call trashes a register you thought was preserved

and suchlike.

It is a work in progress, currently at the proof-of-concept stage.

The current version is 0.2-PRE. It is a complete reboot of SixtyPical 0.1. The reference implementation is written in Python instead of Haskell. The language is much simpler — we're going to try to get the analysis completely right before adding more sophisticated and useful features.

Documentation

• Design Goals — coming soon.
• SixtyPical specification
• [Literate test suite for SixtyPical execution](tests/SixtyPical Execution.md)
• [Literate test suite for SixtyPical analysis](tests/SixtyPical Analysis.md)
• [6502 Opcodes used/not used in SixtyPical](doc/6502 Opcodes.md)

TODO

For 0.3:

• extern routines.
• generate 6502 code (either Ophis assembler or machine code PRG files.)
• while loops.
• a little demo that actually compiles and runs on a C64 emulator.

For 0.4 and/or beyond:

• explicitly-addressed memory locations
• repeat loops.
• add line number (or at least routine name) to error messages.
• hexadecimal literals.
• word type.
• table type constructor and indirect addressing.
• if not.
• 6502-mnemonic aliases (sec, clc)
• other handy aliases (eq for z, etc.)