Python68K_Final_Implementation_Checklist.md

Python68K Final Implementation Checklist

Phase 0 - Bootstrap

• Repository skeleton created
• Host build (GCC/Clang) working
• Amiga build (vbcc) working
• -cpu=68000 -fpu=0 enforced
• Platform abstraction layer implemented
• Tracked allocator implemented
• Type-width assertions implemented
• python -V implemented
• python --help implemented
• Zero warnings in debug builds
• Allocator tests passing

Phase 1 - Tokenizer

• Token definitions complete
• Integer literals
• String literals
• Identifier parsing
• Comment handling
• NEWLINE generation
• INDENT generation
• DEDENT generation
• Tab rejection in indentation
• Line/column tracking
• EOF token generation
• Tokenizer test suite passing

Phase 2 - Parser & AST

• AST arena allocator implemented
• Pratt expression parser implemented
• Statement parser implemented
• Operator precedence verified
• Function parsing implemented
• Loop parsing implemented
• Slice parsing implemented
• Grammar compliance tests passing

Phase 3 - Symbol Analysis

• Function prepass implemented
• Duplicate parameter detection
• Local slot assignment
• UNBOUND local support
• Global name classification
• Builtin resolution order implemented
• Context validation (return/break/continue)

Phase 4 - Bytecode Compiler

• Constant pool implementation
• Name table implementation
• String interning
• FNV-1a hashing
• Opcode metadata generation
• Branch patching
• Function code generation
• Control-flow code generation
• Short-circuit logic generation

Phase 5 - Bytecode Verification

• Instruction boundary validation
• Branch validation
• Index validation
• Stack-depth validation
• CFG traversal implemented
• Maximum stack calculation
• Malformed bytecode rejection

Phase 6 - Runtime Values

• Reference-counted objects
• String object
• List object
• Function object
• Native function object
• Ownership rules implemented
• Retain/release APIs implemented
• Leak detection tests passing

Phase 7 - VM Core

• Value stack implemented
• Frame stack implemented
• Global table implemented
• Builtin table implemented
• Opcode dispatch loop implemented
• Error propagation implemented
• Full VM unwind implemented
• Traceback support implemented

Phase 8 - Arithmetic Semantics

• Checked add
• Checked subtract
• Checked multiply
• Checked negate
• Python floor division semantics
• Python modulo semantics
• Overflow tests passing

Phase 9 - Strings, Lists, Range

• String concatenation
• String slicing
• String indexing
• List append
• List pop
• List indexing
• List assignment
• Range implementation
• Cycle detection for lists

Phase 10 - Functions

• Parameter passing
• Local variables
• Recursion
• Explicit return
• Implicit None return
• Call validation

Phase 11 - Builtins

• print
• len
• range
• int
• str
• bool
• abs
• min
• max
• list_append
• list_pop
• exit
• time
• sleep
• ctime
• localtime
• strftime
• perf_counter

Phase 12 - AmigaDOS Integration

• Script execution
• -c execution
• argv support
• Synchronous os.system command execution
• os.popen PIPE: output capture verified on Amiga
• File APIs
• Environment APIs
• Exit-code mapping
• Memory stats output

Quality Gates

• No memory leaks (full make test suite run under ASan/UBSan, zero findings)
• All unit tests pass
• All negative tests pass
• All differential tests pass
• Allocation-failure tests pass
• Host debug build passes
• Host release build passes
• Amiga debug build passes
• Amiga release build passes
• Executes on emulator
• Executes on real 68000 hardware

MVP Acceptance

• python script.py works
• python -c works
• Bytecode VM executes code
• Functions work
• Recursion works
• Strings work
• Lists work
• Tracebacks work
• Unsupported syntax rejected cleanly
• No 68020 instructions present
• No FPU required
• Documentation complete
• Language Level 0.1 frozen

Future / post-0.6

• CPython-style open (option 1): open() + file.read()/write()/close(), limited keyword args for encoding='utf-8' (accept/ignore), FileNotFoundError, keep fopen as alias; driver: examples/wordcount.py