Python to Vlang Transpiler

A robust tool to transpile Python source code into V(vlang) code.

Project maintained by yaskhan Hosted on GitHub Pages — Theme by mattgraham

Supported Features

This document lists all Python language features supported by the transpiler.

Core Language Features

Variables & Types

Feature Status Notes
Basic types (int, float, bool, str) ✅ Direct mapping
Type inference (mypy) ✅ Using static analysis
.pyi stub files ✅ Mypy plugin uses type stubs for accurate static typing
Lists ✅ list[T] → []T
Dictionaries ✅ dict[K, V] → map[K]V
Tuples ✅ Fixed-size tuples → arrays
Sets ✅ set[T] → map[T]bool
Optional types ✅ Optional[T] → ?T
Union types ✅ X \| Y (Python 3.10+)
Type aliases ✅ Including recursive aliases
TypedDict ✅ Both class-based and functional syntax
Literal types ✅ Literal[1, "a"]
Final variables ✅ Final[T]
ClassVar ✅ Class variables
Self type ✅ Python 3.11+, support for generic context (PEP 673 + 695)
Annotated types ✅ Annotated[T, ...]
TypeGuard ✅ Type narrowing
NoReturn ✅ Functions that never return
NewType ✅ Type aliases
ParamSpec ✅ Callable parameters
TypeVar ✅ Generics
Required/NotRequired ✅ TypedDict fields
Unpack ✅ TypedDict unpacking
TypeForm 🧪 PEP 747 (mapped to Any). See limitations below.

Control Flow

Feature Status Notes
if/elif/else ✅ Direct mapping
for loops ✅ Including else clause
while loops ✅ Including else clause
match/case ✅ Structural pattern matching
Guard clauses in match ✅ case x if condition:
OR patterns ✅ case A \| B:
Capture patterns ✅ case Point() as p:
Mapping patterns ✅ {'key': value}
Sequence patterns ✅ [x, y, *rest]
Wildcard pattern ✅ case _:
Class patterns ✅ case Point(x=1)

Functions

Feature Status Notes
Function definitions ✅ With type hints
Arguments (positional) ✅  
Keyword arguments ✅  
*args ✅ Variadic arguments
**kwargs ✅ Keyword variadic arguments
Keyword-only args ✅ def f(*, arg):
Positional-only args ✅ def f(arg, /):
Default values ✅  
Lambda expressions ✅  
Decorators ✅ Including with arguments
Async functions ✅ async def
Generators ✅ yield
Generator delegation ✅ yield from
Async generators ✅ async for, async yield
Bi-directional generators ✅ send(), throw(), close()
singledispatch ✅ functools.singledispatch
Overload decorator ✅ @overload
Type parameters (PEP 695) ✅ Python 3.12+ full support including ParamSpec and TypeVarTuple

Object-Oriented Programming

Feature Status Notes
Class definitions ✅ → V structs
Inheritance ✅ Via struct embedding
Method overriding ✅  
__init__ method ✅ Constructor
__new__ method ✅ Custom instance creation
Operator overloading ✅ __add__, __sub__, etc.
__slots__ ✅ Memory optimization
Properties ✅ @property, setters
Class methods ✅ @classmethod
Static methods ✅ @staticmethod
Abstract methods ✅ Via typing
Metaclasses ✅ class X(metaclass=M)
__init_subclass__ ✅ Hook for subclasses
Protocol (structural) ✅ typing.Protocol
Dataclasses ✅ → V structs
NamedTuple ✅ → V structs
Enum ✅ Including Flag, auto()
Private name mangling ✅ __private → _Class__private
Descriptors ✅ __get__, __set__, __delete__
__getattr__ ✅ Dynamic attributes
hasattr/getattr/setattr ✅  

Expressions & Operators

Feature Status Notes
Arithmetic operators ✅ +, -, *, /, //, %, **
Comparison operators ✅ <, >, <=, >=, ==, !=
Logical operators ✅ and, or, not
Bitwise operators ✅ &, \|, ^, ~, <<, >>
Matrix multiplication ✅ @, @=
Membership operators ✅ in, not in
Identity operators ✅ is, is not
Conditional expressions ✅ x if cond else y
Walrus operator ✅ :=
Chained comparisons ✅ a < b < c
Slice notation ✅ list[1:3]
Slice assignment ✅ list[x:y] = [...]
del statement ✅ Including slices
assert statement ✅  
isinstance ✅ Type checks
type() ✅  

Comprehensions

Feature Status Notes
List comprehensions ✅ [x for x in y]
Dict comprehensions ✅ {k: v for ...}
Set comprehensions ✅ {x for x in y}
Generator expressions ✅ (x for x in y)
Nested comprehensions ✅  
Async comprehensions ✅ [x async for x in y]
Comprehension with if ✅ Filtering
global/nonlocal in comp. ✅ Python 3.13+

Statements & Keywords

Feature Status Notes
global ✅  
nonlocal ✅ (as comments in V)
pass ✅  
break/continue ✅  
return ✅  
raise ✅ Including raise from
try/except/else/finally ✅ Full exception handling
Exception groups ✅ try/except* (3.11+)
with statement ✅ Context managers
Multiple context managers ✅ with a, b:
Async with ✅  
del ✅ Single and multiple targets
import/from import ✅ Including relative imports

String Features

Feature Status Notes
f-strings ✅ Including debug f"{x=}"
Nested f-strings ✅  
Dynamic format specs ✅ f"{x:{y}}"
Raw strings ✅ r"..."
String concatenation ✅ Implicit "a" "b"
% formatting ✅ Legacy operator
.format() ✅ Custom __format__
bytes literals ✅ b"..."
bytearray ✅  

Built-in Functions

Function Status V Mapping
print() ✅ println()
len() ✅ .len
range() ✅ for i in 0 .. n
enumerate() ✅ Helper function
zip() ✅ Helper function
map() ✅ Helper function
filter() ✅ Helper function
any() ✅ Helper function
all() ✅ Helper function
reversed() ✅ Helper function
sorted() ✅ Helper function
input() ✅ io.read_line()
isinstance() ✅ Type assertion
str() ✅ .str()
int() ✅ Type conversion
float() ✅ Type conversion
bool() ✅ Type conversion
list() ✅ Type conversion
dict() ✅ Type conversion
set() ✅ Type conversion
tuple() ✅ Type conversion
sum() ✅ Helper function
min()/max() ✅ Helper function
abs() ✅ math.abs()
round() ✅ math.round()
pow() ✅ math.pow()
divmod() ✅ Helper function
hash() ✅ Helper function
id() ✅ Helper function
repr() ✅ .str()
ascii() ✅ Helper function
bin()/hex()/oct() ✅ Helper function
ord()/chr() ✅ Helper function
open() ✅ os.open() with defer

Standard Library Support

Fully Supported

Module Status Notes
math ✅ All common functions
random ✅ randint, choice, random, seed
json ✅ loads, dumps
time ✅ time, sleep
datetime ✅ datetime.now, date.today
os ✅ Path operations, environment
sys ✅ exit, argv, platform
re ✅ Basic regex operations

Partially Supported

Module Status Notes
collections ⚠️ defaultdict, Counter, OrderedDict
itertools ⚠️ Common functions
functools ⚠️ partial, singledispatch, lru_cache
typing ✅ Most typing constructs
dataclasses ✅ Field definitions
enum ✅ Enum, Flag, auto()
pydantic ✅ BaseModel, Field validation and alias support
pathlib ⚠️ Basic Path operations
io ⚠️ StringIO, basic I/O
logging ⚠️ Basic logging
argparse ⚠️ Basic argument parsing
unittest ⚠️ Test structure
subprocess ⚠️ Basic process execution
socket ⚠️ Basic socket operations
http.client ⚠️ HTTP requests
urllib ⚠️ URL parsing
csv ⚠️ CSV reading/writing
sqlite3 ⚠️ Database operations
threading ⚠️ Basic threading
multiprocessing ⚠️ Process spawning
hashlib ⚠️ Hash functions
uuid ⚠️ UUID generation
base64 ⚠️ Encoding/decoding
struct ⚠️ Binary packing
array ⚠️ Typed arrays
copy ⚠️ copy, deepcopy
pickle ⚠️ Serialization
zlib/gzip ⚠️ Compression
decimal ⚠️ Decimal arithmetic
fractions ⚠️ Fraction operations
statistics ⚠️ Statistical functions
contextlib ⚠️ Context managers
shutil ⚠️ File operations
tempfile ⚠️ Temporary files
platform ⚠️ Platform info

Python Version Support

Python Version Status Notes
3.10 ✅ Minimum supported version
3.11 ✅ Full support
3.12 ✅ PEP 695 type parameters
3.13 ✅ Latest features
3.14+ ⚠️ Experimental (future syntax)

Legend

Type Reification Limitations (PEP 747)

Python’s PEP 747 introduces TypeForm[T] to annotate values that represent a type itself. In V, there is no direct equivalent for runtime type reification that matches Python’s dynamic nature.

Currently, the transpiler maps TypeForm[T] to the V Any sum type. This allows the code to compile and run, but loses the static type-checking guarantees that Python’s type checkers (like mypy) provide for TypeForm. Use this feature with caution and ensure that runtime type checks are performed if necessary.