simple-parsing allows you to transform your ugly argparse scripts into beautifully structured, strongly typed little works of art. This isn't a fancy, complicated new command-line tool either, this simply adds new features to plain-old argparse!
Using dataclasses, simple-parsing makes it easier to share and reuse command-line arguments - no more copy pasting!
Supports inheritance, nesting, easy serialization to json/yaml, automatic help strings from comments, and much more!
# examples/demo.py
from dataclasses import dataclass
from simple_parsing import ArgumentParser
parser = ArgumentParser()
parser.add_argument("--foo", type=int, default=123, help="foo help")
@dataclass
class Options:
""" Help string for this group of command-line arguments """
log_dir: str # Help string for a required str argument
learning_rate: float = 1e-4 # Help string for a float argument
parser.add_arguments(Options, dest="options")
args = parser.parse_args()
print("foo:", args.foo)
print("options:", args.options)$ python examples/demo.py --log_dir logs --foo 123
foo: 123
options: Options(log_dir='logs', learning_rate=0.0001)$ python examples/demo.py --help
usage: demo.py [-h] [--foo int] --log_dir str [--learning_rate float]
optional arguments:
-h, --help show this help message and exit
--foo int foo help (default: 123)
Options ['options']:
Help string for this group of command-line arguments
--log_dir str Help string for a required str argument (default:
None)
--learning_rate float
Help string for a float argument (default: 0.0001)For a simple use-case, where you only want to parse a single dataclass, you can use the simple_parsing.parse or simple_parsing.parse_known_args functions:
options: Options = simple_parsing.parse(Options)
# or:
options, leftover_args = simple_parsing.parse_known_args(Options)pip install simple-parsing
API Documentation (Under construction)
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As developers, we want to make it easy for people coming into our projects to understand how to run them. However, a user-friendly
--helpmessage is often hard to write and to maintain, especially as the number of arguments increases.With
simple-parsing, your arguments and their descriptions are defined in the same place, making your code easier to read, write, and maintain. -
(no more copy-pasting)
When you need to add a new group of command-line arguments similar to an existing one, instead of copy-pasting a block of
argparsecode and renaming variables, you can reuse your argument class, and let theArgumentParsertake care of adding relevant prefixes to the arguments for you:parser.add_arguments(Options, dest="train") parser.add_arguments(Options, dest="valid") args = parser.parse_args() train_options: Options = args.train valid_options: Options = args.valid print(train_options) print(valid_options)
$ python examples/demo.py \ --train.log_dir "training" \ --valid.log_dir "validation" Options(log_dir='training', learning_rate=0.0001) Options(log_dir='validation', learning_rate=0.0001)
These prefixes can also be set explicitly, or not be used at all. For more info, take a look at the Prefixing Guide
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It's easy to choose between different argument groups of arguments, with the
subgroupsfunction! -
Default values for command-line arguments can easily be read from many different formats, including json/yaml!
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Easily save/load configs to
jsonoryaml!. -
You can easily customize an existing argument class by extending it and adding your own attributes, which helps promote code reuse across projects. For more info, take a look at the inheritance example
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Dataclasses can be nested within dataclasses, as deep as you need!
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This is sometimes tricky to do with regular
argparse, butsimple-parsingmakes it a lot easier by using the python's builtin type annotations to automatically convert the values to the right type for you. As an added feature, by using these type annotations,simple-parsingallows you to parse nested lists or tuples, as can be seen in this example -
(More to come!)
Additional examples for all the features mentioned above can be found in the examples folder
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