predecessor

Overview

This set of libraries is intended to provide useful classes to inherit from, in a way that is cross compatible between multiple languages. A version of this library is currently available in:

Python (2 or 3)
Javascript

The libraries currently provide:

singleton objects
serializable objects

Singleton

The singleton class provides a way to ensure you only have one instance of a class. For instance:

from predecessor import Singleton


class Example(Singleton):
    def __init__(self, foo, bar):
        self.foo = foo
        self.bar = bar


a = Example(3, 8)
b = Example(2, 9)
a is b  # returns True
a.foo == b.foo == 3  # returns True

Or equivalently in Javascript:

const Singleton = require('predecessor').Singleton;

class Example extends Singleton {
    constructor(foo, bar)   {
        this.foo = foo;
        this.bar = bar;
    }
}

let a = new Example(3, 8);
let b = new Example(2, 9);
a === b;  // returns true
a.foo === 3;  // returns true
b.foo === 3;  // returns true

Serializable

The singleton class provides a way to serialize a class without needing to care about what form the resulting blob takes. If a compatible class definition is available in all supported languages, it should be deserializable in all supported languages.

The Basic Case

from predecessor import Serializable


class Example(Serializable):
    def __init__(self, foo, bar):  # Note that keyword args are not supported
        self.foo = foo
        self.bar = bar

    def serialized(self):
        return super(Example, self).serialized(self.foo, self.bar)


a = Example(3, 8)
b = Example.deserialize(a.serialized())
a.foo == b.foo == 3  # returns True
a.bar == b.bar == 8  # returns True

Or equivalently in Javascript:

const Serializable = require('predecessor').Serializable;

class Example extends Serializable {
    constructor(foo, bar)   {
        this.foo = foo;
        this.bar = bar;
    }

    serialized()    {
        return super.serialized(this.foo, this.bar);
    }
}

let a = new Example(3, 8);
let b = Example.deserialize(a.serialized());
a.foo === 3;  // returns true
b.foo === 3;  // returns true
a.foo === 8;  // returns true
b.foo === 8;  // returns true

Implied Serialization

In both languages, you can also use implied serialization. This looks like:

class Example(Serializable):
    __slots__ = ('a', 'b', 'c')

    def __init__(self, a, b, c):
        self.a = a
        self.b = b
        self.c = c

class Example extends Serializable  {
    constructor(a, b, c)    {
        super();
        this._slots = ['a', 'b', 'c'];
        this.a = a;
        this.b = b;
        this.c = c;
    }
}

Advanced Recombination

In both languages you can do data processing before feeding things into your constructor.

class Example(Serializable):
    def __init__(self, a, b, c):
        self.a = a
        self.b = b
        self.c = c

    def serialized(self):
        return super(Example, self).serialized(self.a, self.b)

    @classmethod
    def recombine(cls, a, b):
        return cls(a, b, a+b)

class Example extends Serializable  {
    constructor(a, b, c)    {
        super();
        this.a = a;
        this.b = b;
        this.c = c;
    }

    serialized()    {
        return super.serialized(this.a, this.b);
    }

    static recombine(a, b)  {
        return new this(a, b, a+b);
    }
}

Release files for predecessor 0.0.3

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for predecessor 0.0.3
File	Size	Uploaded
predecessor-0.0.3.tar.gz	2.8 kB	May 12, 2018	Details

Built distribution (wheel)

Table of built distributions (wheels) for predecessor 0.0.3
File	Interpreter	ABI	Platform	Reset
predecessor-0.0.3-py2.py3-none-any.whl 4.4 kB May 12, 2018	Python 2, Python 3	none	any	Details

Total release size:7.2 kB

Release files / predecessor-0.0.3.tar.gz

Download URL	predecessor-0.0.3.tar.gz
Size	2.8 kB
Tags	Source
SHA-256 checksum How to use checksums	`64d5681481d56765145c0c6afde07302405dca2d34acdd71650928890a8f73b1`
BLAKE2b-256 checksum How to use checksums	`583879b3aa3eaa4caa654d0da932613825121a6266ba21d1ea32784a0d58e318`
Upload date	May 12, 2018
Uploaded using Trusted Publishing? What is trusted publishing?	No

Release files / predecessor-0.0.3-py2.py3-none-any.whl

Download URL	predecessor-0.0.3-py2.py3-none-any.whl
Size	4.4 kB
Tags	Python 2 Python 3
SHA-256 checksum How to use checksums	`7c8def70350fa26bb5f3ceb049942d6eecc902f1c0fc7b057720c2efb02e8022`
BLAKE2b-256 checksum How to use checksums	`218f7c45e1f57cd9e0d806f2df31b3d0104a890ab5430d9a6bea9d37c4554d80`
Upload date	May 12, 2018
Uploaded using Trusted Publishing? What is trusted publishing?	No