65 notes
v0.10 cycle GC port. Maps Python/gc.c, Python/gc_gil.c, Python/object_stack.c, Objects/weakrefobject.c onto gopy/gc and objects/weakref. Defines what '100% behavioural compatibility' means when the host runtime is Go (which already collects cycles).
Specification series for gopy — a port of CPython's Python/ runtime to Go with 100% behavioural compatibility.
Technical specifications and design documents for ongoing projects.
Phased milestone plan from v0.0.1 (parser smoke) to v1.0 (full CPython parity). Defines the ordering of subsystem ports and the gating criteria for each release.
Top-level overview of the gopy project. Ports CPython's Python/ runtime to Go with 100% behavioural compatibility.
Internal time utilities. Ports cpython/Python/pytime.c. Provides PyTime_t (int64 nanoseconds), monotonic / perf / wall clocks, double / timespec / timeval conversions, deadline math.
Bytecodes ported in v0.9 that finish the Tier-1 panel: import, generator, pattern-match, with/finally, set builders, and the async-protocol stubs.
Public TokenizerIter wrapper. Ports Python-tokenize.c. The actual lexer lives in cpython/Parser/tokenizer/ and is covered by the parser spec series.
PEP 567 contextvars. Ports cpython/Python/context.c plus _contextvars.c. Uses the HAMT (1662) as backing store.
Two small infra ports - getopt.c (CLI option parser used during interpreter init) and hashtable.c (generic _Py_hashtable_t internal hash table). Bundled because each is tiny and self-contained.
Hash Array Mapped Trie immutable mapping. Backs contextvars (1663). Ports cpython/Python/hamt.c byte-for-byte preserving the 5-bit-per-level tree shape.
Top-level overview of the gopy Objects port. Ports cpython/Objects/ to Go with 100% behavioural compatibility. Lives in the 1670-1689 block of the 1600 spec series.
Port of cpython/Python/marshal.c (2163 lines) to the marshal/ package. Full type-tag dispatch, TYPE_LONG arbitrary-precision encoding, FLAG_REF back-reference dedup, TYPE_CODE read/write, and .pyc file header. Gates the v0.8 milestone.
Port of cpython/Python/codecs.c (1708 lines) to the codecs/ package. Codec registry, error-handler registry, Encode/Decode entry points, and the three built-in codecs (utf-8, ascii, latin-1) needed by the import source reader.
Port of cpython/Python/import.c (4956 lines) and Python/frozen.c (132 lines). Frozen module loader, sys.modules lookup, source and bytecode loaders, builtin module table, and the IMPORT_NAME / IMPORT_FROM / IMPORT_STAR bytecodes. Gates v0.8.
Port of cpython/Python/bltinmodule.c (subset), sysmodule.c (subset), _warnings.c, and the _contextvars hook. The minimum builtins/sys surface v0.7 needs to ship.
Port of cpython/Python/pythonrun.c. PyRun_SimpleString, PyRun_File, the REPL loop, and the .pyc read/write helpers that the lifecycle calls.
Port of cpython/Python/pylifecycle.c, preconfig.c, initconfig.c, interpconfig.c, pathconfig.c. Py_Initialize / Py_Finalize and the config plumbing they consume.
Top-level overview of the gopy VM (Tier-1 bytecode interpreter) port. Covers ceval, ceval_macros, ceval_gil, frame, stackrefs, and the bytecodes DSL output. Lives in the 1630-1639 block.
Port of cpython/Python/ceval.c and cpython/Python/ceval_macros.h. The Tier-1 bytecode dispatch loop, exception unwind, generator resume, and call/return trampolines.
Port of cpython/Python/ceval_gil.c. The GIL acquire/release protocol, the eval breaker bitfield, signal pending flags, and the gopy-vs-Go-runtime threading mapping.
Port of cpython/Tools/cases_generator. Reads Python/bytecodes.c, emits the Go dispatch table at vm/opcodes_gen.go and metadata at compile/opcodes_gen.go.
Port of cpython/Python/stackrefs.c. Tagged stack reference values, borrow tracking, and the conversion shims between PyObject* and stackref.
Port of cpython/Python/intrinsics.c. The CALL_INTRINSIC_1 / CALL_INTRINSIC_2 dispatch tables that back compile-time-emitted runtime helpers (print expr, list-to-tuple, import-star, type-alias).
Port of cpython/Python/frame.c. Frame layout, locals-plus storage, frame chain push/pop, generator frame suspension.
Top-level overview of the gopy Parser port. Covers the PEG parser, lexer, tokenizer drivers, string literal parser, error helpers, and readline. Lives in the 1640-1645 block of the 1600 spec series.
Port of cpython/Parser/pegen_errors.c, action_helpers.c, peg_api.c, and token.c. SyntaxError text panel, AST construction helpers, and the token table.
Port of cpython/Parser/lexer/ and cpython/Parser/tokenizer/. Lexer state machine, buffer, token emission, and the four tokenizer drivers (file, string, utf8, readline).
Port of cpython/Parser/pegen.c and the generated cpython/Parser/parser.c. PEG runtime plus the parser table that turns a token stream into an AST.
Port of cpython/Parser/string_parser.c. Decodes Python string, bytes, f-string, and t-string literals into AST nodes. Handles escape sequences, prefixes, and f-string interpolation re-entry.
Port of the remaining cpython/Objects/ files. weakref, memoryview, file, picklebuffer, typevar / TypeAliasType, union, GenericAlias, Interpolation / Template, plus the obmalloc stub.
Port of cpython/Objects/moduleobject.c, namespaceobject.c, structseq.c, capsule.c, iterobject.c, and enumobject.c. Module, SimpleNamespace, structseq, Capsule, the generic iterator wrappers, and enumerate / reversed.
Port of cpython/Objects/codeobject.c, frameobject.c, genobject.c, and cellobject.c. The four objects the VM thinks in: bytecode, execution frame, generator state machine, and closure cells.
Port of cpython/Objects/exceptions.c. The full BaseException hierarchy with the args slot byte-equal to CPython for every constructor.
Port of cpython/Objects/descrobject.c, methodobject.c, classobject.c, and funcobject.c. The descriptor protocol (data and non-data), bound methods, builtin function objects, and Python function objects.
Port of cpython/Objects/call.c. Vectorcall fast path, generic call dispatch, argument tuple construction, and the kwargs handling rules.
Port of cpython/Objects/abstract.c. Cross-type protocol dispatch (PyObject_*, PyNumber_*, PySequence_*, PyMapping_*, PyIter_*) that the bytecode interpreter calls into.
Port of cpython/Objects/sliceobject.c and rangeobject.c. The slice and range builtins, plus the Ellipsis singleton.
Port of cpython/Objects/setobject.c. set and frozenset on the same open-addressing layout as dict, sharing the probing sequence.
Port of cpython/Objects/dictobject.c and odictobject.c. Insertion-ordered open-addressing hash table with the CPython probing sequence.
Port of cpython/Objects/listobject.c. Mutable variable-length sequence with the CPython list_resize growth curve and Timsort.
Port of cpython/Objects/tupleobject.c. Immutable sequence with the empty-tuple singleton and the CPython tuple hash.
Port of cpython/Objects/unicodeobject.c and unicodectype.c. PEP 393 kind-tagged str with the full method surface and Unicode classification tables.
Port of cpython/Objects/bytesobject.c, bytearrayobject.c, and bytes_methods.c. Immutable bytes plus mutable bytearray with the full string-like method panel.
Port of cpython/Objects/boolobject.c plus the None and NotImplemented singletons. bool is a subtype of int.
Port of cpython/Objects/floatobject.c and complexobject.c. IEEE-754 binary64 float with shortest-roundtrip repr, plus the complex builtin used by cmath.
Port of cpython/Objects/longobject.c. Arbitrary-precision int with the small-int cache, base-2/8/10/16 parsing, hash, and the full numeric protocol.
Port of cpython/Parser/myreadline.c. Cross-platform readline shim used by the interactive REPL. Mostly a thin wrapper over the host readline library; gopy substitutes Go-native line editing.
Type, slots, MRO, lookup. Mirrors PyTypeObject from cpython/Include/cpython/typeobject.h.
Object interface, Header, VarHeader, refcount, and identity. Mirrors PyObject and PyVarObject in cpython/Include/object.h.
AST, future flags, symbol table, codegen, flowgraph, assemble. Ports asdl.c, Python-ast.c, ast.c, ast_preprocess.c, ast_unparse.c, future.c, symtable.c, instruction_sequence.c, codegen.c, flowgraph.c, assemble.c, compile.c.
Disassembly-golden corpus for the v05test gate. Each fixture is a Go-built AST plus a checked-in .golden file with the expected dis.dis output. Refresh via `go test -update`.
One-line per CPython source file, with the target Go package path and a short purpose note. Canonical lookup table for porters.
Detailed port plan for cpython/Python/codegen.c (~6500 lines) to compile/codegen.go. Statement and expression visitors, frame block stack, pattern matching panel, with-statement state machine, deferred annotations, PEP 695 type-parameter codegen, comprehensive test plan.
Detailed port plan for cpython/Python/assemble.c (~800 lines) to compile/assemble.go. Sequence-to-Code conversion, line table varint format, exception table varint format, co_consts/names/varnames/freevars/cellvars layout, fastlocalskinds, comprehensive test plan.
Detailed port plan for cpython/Python/flowgraph.c (~4200 lines) to compile/flowgraph.go. CFG construction, optimization passes (jump threading, dead-code, const fold, swaptimize, super-instructions), stackdepth, exception handler labelling, comprehensive test plan.
Per-package test plan covering every checklist item in 1620 (compile pipeline) and 1665 (tokenize). Each entry maps a CPython source range to the Go test that locks parity.
Port of cpython/Python/pyhash.c. SipHash-1-3 plus FNV-1a, secret seed bootstrap from 1607.
Locale-independent string and number conversion. Ports pyctype.c, pystrcmp.c, mystrtoul.c, pystrtod.c, dtoa.c, pystrhex.c, pymath.c, pyfpe.c, formatter_unicode.c.
Port of cpython/Python/errors.c and the gating subset of cpython/Objects/exceptions.c. Exception types, set/get/clear, raise/chain, normalize.
Port of cpython/Python/lock.c, parking_lot.c, and critical_section.c into the gopy/pysync package. Address-keyed parking, byte-flag PyMutex, PyEvent, PyOnceFlag, RecursiveMutex, RWMutex, SeqLock, and the PEP 703 critical-section stack.
Port of the seed-init half of cpython/Python/bootstrap_hash.c to gopy/hash. PYTHONHASHSEED parsing, the LCG used when a seed is given, and an OS-entropy fallback. The full SipHash-1-3 / FNV / x86_aes hashing land in v0.4.
Port of cpython/Python/thread.c to gopy/pythread. Thread create, join, ident, and stack-size hooks layered over Go's goroutine scheduler. The OS-specific thread_pthread.h / thread_nt.h files are dropped.
Faithful port of cpython/Python/pyarena.c to gopy/arena. Bump-allocator with linked-block layout used by the compiler pipeline for AST and scratch buffers.
Mechanical translation rules for converting CPython C identifiers to Go-idiomatic names while preserving 1:1 semantics.