SixtyPical/HISTORY.markdown

History of SixtyPical

0.7

• User-defined byte locations can be given an initial value.
• word type locations which can be defined and copyed between.
• Can copy directly from one user-defined byte location to another.

0.6

• Added routine and vector types, and copy instruction.
• Both routines and vectors can declare inputs, outputs, and trashes, and these must be compatible to assign a routine or vector to a vector.
• Added goto (tail call) instruction, jumps to routine or through vector.
• call can call a subroutine indirectly, via a vector.
• Routine name is now shown in analysis error messages.

0.5

• Added byte table type locations and indexed addressing (+ x, + y).
• Integer literals may be given in hexadecimal.
• Line comments may be included in source code by prefixing them with //.

0.4

• Added repeat loops to the language, which can repeat until a flag is set (or not set), or which can repeat forever.
• if not inverts the sense of the test.
• Added explicitly-addressed memory locations.

0.3

• Added external routine declarations.
• Added ability to compile to 6502 machine code and output a PRG file.

0.2

A complete reboot of SixtyPical 0.1. The reference implementation was rewritten in Python. The language was much simplified. The aim was to get the analysis completely right before adding more sophisticated and useful features in future versions.

0.1

Initial inspired-but-messy version implemented in Haskell.