Skip to main content
This is a pre-production deployment of Warehouse. Changes made here affect the production instance of PyPI (
Help us improve Python packaging - Donate today!

A simple Javascript expression builder written for Python.

Project Description


synopsis:A silly little JS expression builder to let you use native Python to build Javascript expression strings.

This package only allows the creation of simple (that is, non-assignment) Javascript expressions using an intuitive Python DSL.

Logical Expressions

>>> from jexp import J
>>> e = J('var_1') & J('var_2')
>>> str(e)


>>> str(e | 'abc')


The argument to the J class will be output as a str in the resulting JS- so J('my_var') is a good way to refer to a var, and J(5) to the number literal 5. If you need an actual string, you can either add the quotes yourself in the J call - J('"my string"') - or otherwise combine the J object with a str, as shown above.

Mathematical Expressions

>>> str(J(5) + 28)


>>> str(J('my_var') + 28)


Division hasn’t been implemented, but other things you expect are there.


>>> e = J(5) <= 6
>>> str(e)


>>> str(e == "test_string")


Attribute Access

>>> e = J('my_var').attribute
>>> str(e)


This should work for any attribute that doesn’t start with an underscore (and some that do).

Function Calling

>>> e = J('func')('a','b')
>>> str(e)


You can also try this with other J objects.

>>> str(J('func')(J('arg1'),J('arg2')))


Release History

This version
History Node


History Node


History Node


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
(3.8 kB) Copy SHA256 Hash SHA256
Source None Sep 2, 2011

Supported By

Elastic Elastic Search Pingdom Pingdom Monitoring Dyn Dyn DNS Sentry Sentry Error Logging CloudAMQP CloudAMQP RabbitMQ Heroku Heroku PaaS Kabu Creative Kabu Creative UX & Design Fastly Fastly CDN DigiCert DigiCert EV Certificate Google Google Cloud Servers