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Nim Package of the Week: nimpy

nimpy is a package for Nim to allow bidirectional integration between Python and Nim. This lets you write functions in Nim and call them from Python and vice versa.

I've used nimpy several times to speed up tight loops or together with last weeks NPOTW npeg to write fast parsers to use from Python without having to get down and dirty in C.

Examples speak more than words, here is a nimpy example from its README:

# mymodule.nim - file name should match the module name you're going to import from python
import nimpy

proc greet(name: string): string {.exportpy.} =
  return "Hello, " & name & "!"

When you build the above module with nim c --threads:on --app:lib mymodule and then place it on your import path for Python you can use it:

import mymodule
assert mymodule.greet("world") == "Hello, world!"
assert mymodule.greet(name="world") == "Hello, world!"

The offered speedups to get C speed of execution while still having a higher level language to write your code in should lessen the step when deciding to fork out some performance critical bits of your Python to another language!

The Nim Package of the Week is a series on Nim packages that make up the ecosystem where a new article appears weekly on a library that you should know about.