Skip to main content

Decorator that allows you to specify the valid types of the parameters in a function or method.

Project description

What

Decorator that allows you to specify the valid types of the parameters in a function or method.

In case of that a call don’t match the required type will fail with a TypeError exception.

Why?

There are some cases (TODO: add some examples) where you want/need to specify a specific type to use and since python does not have type checks for parameters here’s where this is useful.

All the existing solutions that I’ve found had some problem or does not have a feature that I’d like to have, so I’ve made my own.

How to use?

First, install the RequireType package, you can do that using pip::
pip install requiretype

In your code you just need to import and use the require decorator.

Example:

from requiretype import require

@require(name=str, age=(int, float, long))
def greet_person(name, age):
    print "Hello {0} ({1})".format(name, age)

>>> greet_person("John", 42)
Hello John (42)

>>> greet_person("John", "Doe")
[...traceback...]
TypeError: Doe is not a valid type.
Valid types: <type 'int'>, <type 'float'>, <type 'long'>

>>> greet_person(42, 43)
[...traceback...]
TypeError: 42 is not a <type 'str'> type

Some notes

Here are some details about this library. Most of them was found in one or more packages that helps you to enforce/check/require types and IMO are not good things to have and motivated me to write this.

RequireType:

  • does not modify args or kwargs
  • does not move arguments from one place to another
  • support both args and kwargs
  • allows you to use all the python 2.x supported parameters usage (if not, please report a bug)
  • use named arguments type definition
  • allows you to enforce a subset of all the available arguments
  • raise a standard TypeError if the arguments type are wrong

Project details


Release history Release notifications

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Filename, size & hash SHA256 hash help File type Python version Upload date
RequireType-0.1.0.tar.gz (3.4 kB) Copy SHA256 hash SHA256 Source None Sep 28, 2015

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page