Intro to Python

Goals

It's time to learn a new language! Python!

Python is a popular, easy-to-use programming language that has significant traction in the field.

Remember the goal is learning to learn, so keep track of what works for you and what doesn't as you go through the process of exploring Python.

Techniques for learning new languages

• Try to relate things you already know in another language (e.g. what an array is) to the corresponding things in Python (e.g. a list) and how to use them.

• Write a bunch of "toy programs" that demonstrate different key features of the language

• Explore the standard library that's available for the language. Skim it briefly for now--the idea isn't to memorize everything but to file away generally what functionality is available.

• Write a more substantial toy program that uses a variety of the features.

Again, keep track of what works for you. Try different things to see what works best for learning new languages.

Resources

• Installing Python and pipenv
• JavaScript<->Python cheatsheet
• How to read Specs and Code
• Python 3 standard library
• Style Guide for Python Code

Getting started

1. Make sure you have Python 3 and pipenv installed.

2. Go to the directory with the Pipfile and run

   pipenv install
   

3. After the install completes, run

   pipenv shell
   

   This will get you into the virtual environment. At this point, you should be able to run Python 3 by just running python:

   $ python --version
   Python 3.6.5
   

   You can exit the virtual environment by typing exit.

Day 1

Goals

• Learn the basic syntax and structure of Python

Summary

• Implement a number of tiny Python programs that demonstrate Python syntax.

Instructions

Take a look in the src/ directory.

NOTE: adv/ is for Day 2, so ignore it for today.

Suggested order for implementing the toy programs:

• hello -- Hello world
• bignum -- Print some big numbers
• datatypes -- Experiment with type conversion
• modules -- Learn to import from modules
• printf -- Formatted print output
• lists -- Python's version of arrays
• tuples -- Immutable lists typically for heterogenous data
• slice -- Accessing parts of lists
• comp -- List comprehensions
• dicts -- Dictionaries
• func -- Functions
• args -- Arguments and Keyword Arguments
• scope -- Global, Local, and Non-Local scope
• fileio -- Read and write from files
• cal -- Experiment with module imports
• obj -- Classes and objects

Day 2

Goals

• Solidify the Python basics

Summary

• Implement a basic text adventure game
• Add classes for rooms and the player
• Add a simple parser that reads user input and performs actions

Instructions

This is in src/adv/. Check it out!

• Put the Room class in room.py based on what you see in adv.py.

• Put the Player class in player.py.

• Follow the instructions adv.py.

• Figure out what all those .pyc files are that appear after you successfully run the program.

Day 3

Goals

• Prepare for more OOP techniques
• Practice classes and lists

Summary

• Add items to the game that the user can carry around
• Make rooms able to hold multiple items
• Make the player able to carry multiple items
• Add two-word commands to the parser
• Add the get and drop commands to the parser

Instructions

• Add an Item class in a file item.py.

  • This will be the base class for specialized item types to be declared later.

  • The item should have name and description attributes.

    • Hint: the name should be one word for ease in parsing later.

• Add capability to add items to rooms.

  • The Room class should be extended with a list that holds the Items that are currently in that room.

  • Add functionality to the main loop that prints out all the items that are visible to the player when they are in that room.

• Add capability to add Items to the player's inventory. The inventory can also be a list of items "in" the player, similar to how Items can be in a Room.

• Add a new type of sentence the parser can understand: two words.

  • Until now, the parser could just understand one sentence form:

    verb

    such as "n" or "q".

  • But now we want to add the form:

    verb object

    such as "take coins" or "drop sword".

  • Split the entered command and see if it has 1 or 2 words in it to determine if it's the first or second form.

• Implement support for the verb get followed by an Item name. This will be used to pick up Items.

  • If the user enters get or take followed by an Item name, look at the contents of the current Room to see if the item is there.

    • If it is there, remove it from the Room contents, and add it to the Player contents.

    • If it's not there, print an error message telling the user so.

• Implement support for the verb drop followed by an Item name. This is the opposite of get/take.

• Add the i and inventory commands that both show a list of items currently carried by the player.

Day 4

Goals

• Practice inheritance
• Practice method overriding
• Be able to call superclass methods
• Implement a callback/event structure

Summary

• Add scoring
• Subclass items into treasures
• Subclass items into light sources
• Add methods to notify items when they are picked up or dropped
• Add light and darkness to the game

Instructions

• Add a score to your Player class. Set it to 0.

• Add a single word command, score, that the user can type in to see their current score.

• Add a subclass to Item called Treasure.

  • The Treasure constructor should accept a name, description, and value.

• During world creation, add three Treasures to convenient Rooms.

• Add an on_take method to Item.

  • Call this method when the Item is picked up by the player.

  • The Item can use this to run additional code when it is picked up.

• Override on_take in Treasure so that the player gets the value of the Treasure added to their score attribute but only the first time the treasure is picked up.

  • If the treasure is dropped and picked up again later, the player should not have the value added to their score again.

• Add an on_drop method to Item. Implement it similar to on_take.

• Add a subclass to Item called LightSource.

• During world creation, add a lamp LightSource to a convenient Room.

• Override on_drop in LightSource that tells the player "It's not wise to drop your source of light!" if the player drops it. (But still lets them drop it.)

• Add an attribute to Room called is_light that is True if the Room is naturally illuminated, or False if a LightSource is required to see what is in the room.

• Modify the main loop to test if there is light in the Room (i.e. if is_light is True or there is a LightSource item in the Room's contents or if there is a LightSource item in the Player's contents).

  • If there is light in the room, display name, description, and contents as normal.

  • If there isn't, print out "It's pitch black!" instead.

  • Hint: isinstance might help you figure out if there's a LightSource among all the nearby Items.

• Modify the get/take code to print "Good luck finding that in the dark!" if the user tries to pick up an Item in the dark.

Stretch Goals

In arbitrary order:

• Add more rooms.

• Add more items to the game.

• Add a way to win.

• Add more to the parser.

  • Remember the last Item mentioned and substitute that if the user types "it" later, e.g.

    take sword
    drop it
    

  • Add Items with adjectives, like "rusty sword" and "silver sword".

    • Modify the parser to handle commands like "take rusty sword" as well as "take sword".

      • If the user is in a room that contains both the rusty sword and silver sword, and they type "take sword", the parser should say, "I don't know which you mean: rusty sword or silver sword."

• Modify the code that calls on_take to check the return value. If on_take returns False, then don't continue picking up the object. (I.e. prevent the user from picking it up.)

  • This enables you to add logic to on_take to code things like "don't allow the user to pick up the dirt unless they're holding the shovel.

• Add monsters.

• Add the attack verb that allows you to specify a monster to attack.

• Add an on_attack method to the monster class.

• Similar to the on_take return value modification, above, have on_attack prevent the attack from succeeding unless the user possesses a sword item.

• Come up with more stretch goals! The sky's the limit!