Szathmáry László honlapja @ DEIK | Nim2 / Working with command-line arguments

In Python, it's very easy to work with command-line arguments. The arguments are stored in the list sys.argv and it contains the name of the executed program too at index position 0 (like C).

Produce the same output
$ ./v1.py argv[0]: ./v1.py $ ./v1.py hello 42 END argv[0]: ./v1.py argv[1]: hello argv[2]: 42 argv[3]: END	$ ./v1 argv[0]: .../a66-command-line-arguments/v1 $ ./v1 hello 42 END argv[0]: .../a66-command-line-arguments/v1 argv[1]: hello argv[2]: 42 argv[3]: END

Source codes:

Source codes
import sys for i, arg in enumerate(sys.argv): print(f"argv[{i}]: {arg}")	import std/strformat # &"Hello {name}!" import jsystem # !!! own module for i, arg in sys.argv: echo &"argv[{i}]: {arg}"

As you can see, the source codes are almost identical.

The magic is achieved with the jsystem module (my module). Here it is:

import os

## Mimicking Python's ``sys`` module to some extent.
##
## To avoid confusion with the ``system`` module from the stdlib,
## it's called ``jsystem``, which stands for "jabba's system" module.

# #######
# Types #
# #######

type
JabbaSys = tuple
argv: seq[string]

# ######
# Vars #
# ######

proc getArgv(): seq[string] =
result &= getAppFilename()
for i in 1 .. paramCount():
result &= paramStr(i)

var sys*: JabbaSys = (
argv: getArgv()
)
## Mimics Python's ``sys.argv``. It contains the file name and the parameters,
## just like in C or Python.
##
## ``sys.argv`` can be modified in Python, that's why it's a ``var``.

Working with command-line arguments — the Python way

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