jexp 0.1.2

A simple Javascript expression builder written for Python.

jexp

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)

‘(var_1&&var_2)’

>>> str(e | 'abc')

‘((var_1&&var_2)||”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)

‘(5+28)’

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

‘(my_var+28)’

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

Comparisons

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

>>> str(e)

‘(5<=6)’

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

‘((5<=6)==”test_string”)’

Attribute Access

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

>>> str(e)

‘my_var.attribute’

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)

‘func(“a”,”b”)’

You can also try this with other J objects.

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

‘func(arg1,arg2)’