Be synthetic with PySynthetic

PySynthetic is a set of tools that aims to make writing Python classes shorter and "cleaner".

For instance, one can add properties and accessors (getters/setters) to a class with only one line of code (using respectively synthesize_property and synthesize_member decorators), thus making the code more than 5 times shorter (see examples ). One can even avoid the laborious task of members initialization by using the synthesize_constructor decorator that takes care of writing the __init__ method.

PySynthetic is also useful for applying strict type checking with no pain just by using the decorators' contract argument (see PyContracts ).

Help and ideas are appreciated! Thank you!

Resources

• Documentation
• Bug Tracker
• Code
• Mailing List <pysynthetic@googlegroups.com>

Installation

pip install pysynthetic

Or simply from the tarball or source code if you are not using pip.

python setup.py install

Examples

Synthetic properties

With PySynthetic, the following code (8 lines)...

from synthetic import synthesize_constructor, synthesize_property

@synthesize_property('a', contract = int)
@synthesize_property('b', contract = list)
@synthesize_property('c', default = "", contract = str, read_only = True)
@synthesize_constructor()
class ShortAndClean(object):
    pass

... replaces this (43 lines):

from contracts import contract

class ThisHurtsMyKeyboard(object):

    @contract
    def __init__(self, a, b, c = ""):
        """
    :type a: int
    :type b: list
    :type c: str
"""
        self._a = a
        self._b = b
        self._c = c

    @property
    def a(self):
        return self._a

    @a.setter
    @contract
    def a(self, value):
        """
    :type value: int
"""
        self._a = value

    @property
    def b(self):
        return self._b

    @b.setter
    @contract
    def b(self, value):
        """
    :type value: list
"""
        self._b = value

    @property 
    def c(self):
        return self._c

Synthetic accessors

But, if you are more into accessors than properties, you can use synthesize_member decorator instead.

This way, the following code (8 lines)...

from synthetic import synthesize_constructor, synthesize_member

@synthesize_member('a', contract = int)
@synthesize_member('b', contract = list)
@synthesize_member('c', default = "", contract = str, read_only = True)
@synthesize_constructor()
class ShortAndClean(object):
    pass

...will replace this (37 lines):

from contracts import contract

class ThisHurtsMyKeyboard(object):

    @contract
    def __init__(self, a, b, c = ""):
        """
    :type a: int
    :type b: list
    :type c: str
"""
        self._a = a
        self._b = b
        self._c = c

    def a(self):
        return self._a

    @contract
    def set_a(self, value):
        """
    :type value: int
"""
        self._a = value

    def b(self):
        return self._b

    @contract
    def set_b(self, value):
        """
    :type value: list
"""
        self._b = value

    def c(self):
        return self._c