item_49.py

#!/usr/bin/env python3

# Copyright 2014 Brett Slatkin, Pearson Education Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Preamble to mimick book environment
import logging
from pprint import pprint
from sys import stdout as STDOUT


# Example 1
def palindrome(word):
    """Return True if the given word is a palindrome."""
    return word == word[::-1]

assert palindrome('tacocat')
assert not palindrome('banana')


# Example 2
print(repr(palindrome.__doc__))


# Example 3
"""Library for testing words for various linguistic patterns.

Testing how words relate to each other can be tricky sometimes!
This module provides easy ways to determine when words you've
found have special properties.

Available functions:
- palindrome: Determine if a word is a palindrome.
- check_anagram: Determine if two words are anagrams.
...
"""


# Example 4
class Player(object):
    """Represents a player of the game.

    Subclasses may override the 'tick' method to provide
    custom animations for the player's movement depending
    on their power level, etc.

    Public attributes:
    - power: Unused power-ups (float between 0 and 1).
    - coins: Coins found during the level (integer).
    """


# Example 5
import itertools
def find_anagrams(word, dictionary):
    """Find all anagrams for a word.

    This function only runs as fast as the test for
    membership in the 'dictionary' container. It will
    be slow if the dictionary is a list and fast if
    it's a set.

    Args:
        word: String of the target word.
        dictionary: Container with all strings that
            are known to be actual words.

    Returns:
        List of anagrams that were found. Empty if
        none were found.
    """
    permutations = itertools.permutations(word, len(word))
    possible = (''.join(x) for x in permutations)
    found = {word for word in possible if word in dictionary}
    return list(found)

assert find_anagrams('pancakes', ['scanpeak']) == ['scanpeak']