standard-Lib functions ported to Nim (original) (raw)

NimPylib

Write Python in Nim

Nimpylib is a collection of Python-like operators/functions and libraries as well as syntax sugars.

Read Docs|Lib Docs|Wiki about History|Design Wiki

Why NimPyLib?

It helps you to:

use much Python-like out-of-box API in Nim:
- with no need of any Python dependency (neither dynamic library nor binary).
- even handy for ones who don't use much Python but want more functions in Nim
translate your Python program to Nim:
- gaining a right-away speed boot of even 700x
- no worry about binary distribution or packaging, just "compile once, distribute everywhere"
- rid of many annoying runtime-errors (which are turned to compile-time error)
gain a better view into different behaviors between Python and Nim:
- dynamically-typed vs statically-typed
- unconvertible syntax from Python to Nim, e.g.end keyword,not in syntax

Backends

Thanks to Nim supporting multiply backends, pylib currently officially supports to compile to C and JavaScript 1. C++ and ObjC backends are currently not tested.

Demo

import pylib from pylib/Lib/timeit import timeit from pylib/Lib/time import sleep from pylib/Lib/sys import nil # like python's import sys from pylib/Lib/platform import nil # like python's import platform import pylib/Lib/tempfile import pylib/Lib/os

like python's `import tempfile; from tempfile import *`

more python-stdlib in pylib/Lib/...

from now on, we use `>` appended `#` to mean output

print 42 # print can be used with and without parenthesis too, like Python2. #> 42

NOTE: from now on, the following is just valid Python3 code!

only add the following to make it Python:

import platform

from timeit import timeit

from time import sleep

from tempfile import NamedTemporaryFile, TemporaryDirectory

print( f"{9.0} Hello {42} World {1 + 2}" ) # Python-like string interpolation #> 9.0 Hello 42 World 3

class O: @staticmethod def f(): print("O.f")

O.f() #> O.f

def show_range_list(): python_like_range = range(0, -10, -2) print(list(python_like_range)[1:-1]) #> [-2, -4, -6] show_range_list()

Why using so many `def`s?

as in `def`, you can write Nim more Python-like

e.g. nondeclared assignment

and all collection literals becomes Python's type

func definition

typing is suppported and optional

def foo(a: int, b = 1, *args) -> int: def add(a, b): return a + b # nesting for i in args: print(i) return add(a, b)

def show_literals(): ls = [1, 2] # if outside def, ls will be an Nim's array,

which is fixed size and "pass by value"

ls_shallow = ls ls.append(3) assert len(ls_shallow) == 3

s = {"Rachel", "Zack"} # if outside def, s will be an Nim's set,

which only supports small ordinal type as elements

s.add("Zack") assert len(s) == 2

d = { # if outside def, d will be an Nim's array[I, (K, V)], # which even lacks __getitem__ method 'a': "kaneki ken" }

assert d['a'].title() == "Kaneki Ken" # if outside def,

all double-quotation marked literals will be Nim's `string`,

which is more like `bytearray`

and single-quotation marked literals will be Nim's `char`,

which repesents a single byte (ASCII character)

show_literals()

python 3.12's type statement

type Number = float | int # which is originally supported by nim-lang itself, however ;)

for i in range(10): print(i, endl=" ") print("done!") #> 0 1 2 3 4 5 6 7 8 9 done!

Python-like variable unpacking

def show_unpack(): data = list(range(3, 15, 2)) (first, second, *_, last) = data assert (first + second + last) == (3 + 5 + 13)

show_unpack()

if (a := 6) > 5: assert a == 6

print(repr("a".center(9))) #> ' a '

print("" or "b") #> b print("a" or "b") #> a

print(not "") #> True

def show_divmod_and_unpack(integer_bytes): (kilo, bite) = divmod(integer_bytes, 1_024) (mega, kilo) = divmod(kilo, 1_024) (giga, mega) = divmod(mega, 1_024) show_divmod_and_unpack(2_313_354_324)

def lambda_closure(arg): anno = lambda: "hello " + arg return anno() assert lambda_closure("world") == "hello world"

if on Linux:

#assert sys.platform == "linux"

if on x86_64:

#platform.machine == "x86_64"

def allAny(): truty = all([True, True, False]) print(truty) #> False

truty = any([True, True, False]) print(truty) #> True allAny()

def a_little_sleep(): "sleep around 0.001 milsecs."

note Nim's os.sleep's unit is milsec,

while Python's time.sleep's is second.

sleep(0.001)

assert timeit(a_little_sleep, number=1000) > 1.0

Support for Python-like with statements

All objects are closed at the end of the with statement

def test_open(): fn = "nimpylib_test_open_some_file.txt" with open(fn, 'w') as file: _ = file.write("hello world!")

with open(fn, 'r') as file: while True: s = file.readline() if s == "": break print(s)

os.remove(fn)

test_open() #> hello world!

def show_tempfile(): with NamedTemporaryFile() as file: _ = file.write(b"test!") # in binary mode

s="" with TemporaryDirectory() as name: s = name assert len(s) != 0

show_tempfile()

class Example(object): # Mimic simple Python "classes". """Example class with Python-ish Nim syntax!.""" start: int stop: int step: int def init(self, start, stop, step=1): self.start = start self.stop = stop self.step = step

def stopit(self, argument): """Example function with Python-ish Nim syntax.""" self.stop = argument return self.stop

def exa(): e = Example(5, 3) print(e.stopit(5))

exa() #> 5

Nimpylib heavily relies on Nim generics, converters, operator overloading, and even on concepts.

Check the Examples folder for more examples. Have more Macros or Templates for Python-like syntax, send Pull Request.

Installation

If the installing is stuck with:Downloading https://github.com/Yardanico/nimpylib using gitPlease note your nimble package.json is outdated, and that old URL is 404 now 2. Run nimble refresh to fetch a newer package.json

Of course, a workaround is to install with full URL:

nimble install https://github.com/nimpylib/pylib

Uninstall with nimble uninstall pylib.

Requisites

Supported features

F-Strings f"foo {variable} bar {1 + 2} baz"
str bytes bytearray list dict set frozenset() with their methods
Python-like variable unpacking
Math with Float and Int mixed like Python.
lambda:
class Python-like OOP with methods and DocStrings (without multi-inheritance)
@classmethod and @staticmethod
with open(fn, [, ...]): Read, write, append, and read(), seek(), tell(), etc.
super(...).method(...)
global/nonlocal (with some limits)
True / False
pass
del foo[x]
:= Walrus Operator
abs()
all()
any()
ascii()
bin()
chr()
complex()
divmod()
enumerate()
filter()
float()
format()
getattr()
hasattr()
hash()
hex()
id()
input()
int()
isinstance()
issubclass()
iter()
list()
map()
max()
min()
next()
oct()
ord()
open() (though without close_fd, opener, errors)
pow(base, exp, mod=None)
print("foo") / print "foo" Python2 like
range()
reversed(iterable)
round()
hasattr()
set(), also named pyset() to distingish with system.set
slice()
sorted(iterable)
str()
sum()
!= and Python1 <>
long() Python2 like (deprecated)
u"string here" / u'a' Python2 like
b"string here" / b'a'
zip(*iterables, strict=False)
(WIP) standard libraries math, random, datetime, os, tempfile, timeit, ... (see Lib Docs for all supported)
aiter anext and await (yet async def is supported)
More...

Features cannot be implemented

However, due to Nim's AST astrict3, a few syntaxes of Python cannot be implemented.

See here for details and workaround.

Other Python-like modules

serach in nimble
metacraft-labs/py2nim: py2nim transpiler in Nim.
py2many/py2many: py2nim transpiler in Python.
juancarlospaco/cpython: invoke Python Standard Library API in Nim.
yglukhov/nimpy: Python bridge in Nim.

Tests

This is one snippest from version 0.9.5:

as too much tests output is it, and it's not suitable to list too much content in README, the following demo is not likely to be updated from then on.

$ nimble test [Suite] datetime [OK] utcoffset [OK] attrs [OK] isoformat

[Suite] fromisoformat [OK] if reversible

[Suite] timedelta [OK] init [OK] float init [OK] normalize [OK] stringify

[Suite] date [OK] fromisocalendar [OK] fromisocalendar_value_errors [OK] ordinal_conversion [OK] replace [OK] strftime [OK] ctime

[Suite] tzinfo [OK] fromtimestamp

[Suite] gamma [OK] gamma(-integer)

[Suite] ldexp

[Suite] sumprod [OK] array [OK] CPython:test_math.testSumProd

[Suite] constants [OK] nan [OK] inf

[Suite] classify [OK] isinf [OK] isfinite

[Suite] nextafter_ulp [OK] nextafter [OK] ulp

[Suite] ldexp [OK] static [OK] small [OK] non-normal first arg [OK] large second arg

[Suite] ErrnoAttributeTests [OK] using_errorcode [OK] touch, unlink, is_file [OK] Lib/tempfile [OK] Lib/time [OK] Lib/timeit

[Suite] Lib/array [OK] py3.13: 'w' Py_UCS4 [OK] bytes [OK] cmp [OK] byteswap

[Suite] os.path [OK] if export right [OK] getxtime

[Suite] Lib/os with no JS support [OK] mkdir rmdir [OK] open fdopen close [OK] get,set_inheritable [OK] getattr/set/has [OK] bytearray

[Suite] bytes [OK] getitem [OK] meth [OK] repr

[Suite] complex.init(str) [OK] from str [OK] negative_nans_from_string

[Suite] complex [OK] init [OK] literals [OK] str [OK] op

[Suite] complex.repr [OK] (N+nanj) [OK] real == 0.0

[Suite] complex.pow [OK] CPython:test_complex.ComplexTest.test_pow [OK] with small integer exponents [OK] decorator [OK] custom decorator [OK] dict

[Suite] float.fromhex [OK] literals [OK] nans [OK] some values [OK] overflow [OK] zeros and underflow [OK] round-half-even

[Suite] float.fromhex and hex [OK] roundtrip

[Suite] float [OK] hex [OK] test_nan_signs [OK] is_integer [OK] as_integer_ratio

[Suite] rewrite as py stmt [OK] rewrite in def [OK] rewrite raise [OK] Floor division [OK] int.{from,to}_bytes [OK] io & with [OK] bltin iters [OK] iters as iterable [OK] iter/next [OK] random [OK] Lib/string [OK] list shallow [OK] list.sort [OK] list methods [OK] Python-like types [OK] divmod [OK] pass [OK] lambda [OK] walrus operator [OK] hex() [OK] chr() [OK] oct() [OK] ord() [OK] bin() [OK] Modulo operations [OK] int(x[, base]) [OK] float(str) [OK] Range-like Nim procedure [OK] str.format [OK] str operations [OK] str index [OK] str methods [OK] str.maketrans&translate [OK] tonim macro [OK] unpack macro [OK] With statement [OK] generics in func signature [OK] generics in class's methods [OK] set PASS: tests/testaments/builtins/print.nim c ( 1.93 sec) SKIP: tests/testaments/builtins/print.nim js PASS: tests/testaments/builtins/print_ct.nim c ( 1.93 sec) PASS: tests/testaments/builtins/zip_no_seq.nim c ( 1.96 sec) PASS: tests/testaments/builtins/zip_more_args.nim c ( 0.65 sec) PASS: tests/testaments/builtins/filter_toseq_deadloop.nim c ( 0.66 sec) Used D:\software\scoop\shims\nim.exe to run the tests. Use --nim to override. PASS: tests/testaments/pysugar/colonToSlice.nim c ( 2.75 sec) SKIP: tests/testaments/pysugar/colonToSlice.nim js PASS: tests/testaments/pysugar/strlitCat.nim c ( 1.92 sec) SKIP: tests/testaments/pysugar/strlitCat.nim js PASS: tests/testaments/pysugar/tripleStrTranslate.nim c ( 0.84 sec) PASS: tests/testaments/pysugar/autoSetListDict.nim c ( 3.40 sec)

Some of features (listedhere) and Libs (listedhere) is not available for JS backend yet. ↩
see wiki-history for details ↩
Mostly because they cannot form valid AST in Nim. ↩