#!/usr/bin/env python

# We need this for the cross-product we'll use later
import itertools

class Language:
    lang = {}

    def __init__(self):
        pass

    # Input: A meaning, can be any Python object
    # Output: The symbol chosen by the language to represent the meaning
    #    The symbol will not overlap with any other symbol in the language
    def learn(self, meaning):
        pass

    # Input: A meaning
    # Output: The symbol associated with that meaning
    def speak(self, meaning):
        pass

    # Input: A symbol
    # Output: The meaning associated with that symbol
    def hear(self, symbol):
        pass

    def perturb(self):
        pass

class MoreNumbers(Language):
    # Example: A0, B000, D0
    valid_letters =
    pass

class NumberFirst(Language):
    # Example: 0a, 8f, 1s
    pass

class NumberLast(Language):
    # Example: a0, g7, t1
    pass

# Instantiate some languages
langs = [ MoreNumbers(), NumberFirst(), NumberLast() ]

# Here, our 'meanings' are arbitrary, as long as they are common, and each language knows them
# We can just use integers
meanings = range(100)

# Now, teach the languages some stuff
for m in meanings:
    for l in langs:
        l.learn(m)

# Now we want to do a quick check that for each meaning, there's no overlap
# If we've build out languages properly, that should be true.
for m in meanings:
    for l1, l2 in itertools.product(lang):
        # If it's the same language for both the speaker and listener, we expect it
        # to work out
        if l1 == l2:
            heard_meaning = l2.hear(l1.speak(m))
            if heard_meaning != meaning:
                print "Language %s didn't understand %s properly" % (str(type(l1)), str(m))
        # If it's different languages, this should fail
        else:
            heard_meaning = l2.hear(l1.speak(m))
            if heard_meaning != None:
                print "Language %s successfully heard %s spoken by %s" (str(type(l2)), str(m), str(type(l1)))