Skip to main content

Code a toy

Summary

Objectives

By the end of this session you should be able to:

  • Demonstrate that a program can:
    • Receive interactive user input
    • Store data in memory
    • Output data to the screen

Key Points

  • A program can receive user input interactively using an input statement
  • A program can store data in variables of various types
  • A program can output data to the screen using a print statement

Breakdown

Mad Libs

Mad Libs is a word game where you have to fill in the blanks in a given sentence; each blank is given a category. Example:

<name> started their first Generation course today. They are training as a <job name>. They found their cohort to be very <adjective> but their teacher was, at least, <adjective>. For lunch they have <food> and <food> while reviewing their notes. They feel <feeling> but are determined to complete the course.

This could be filled in seriously:

Max started their first Generation course today. They are training as a Software Engineer. They found their cohort to be very overwhelming but their teacher was, at least, understandable. For lunch they have pizza and chips while reviewing their notes. They feel apprehensive but are determined to complete the course.

Or humourously:

Tomato started their first Generation course today. They are training as a Tomato. They found their cohort to be very tomato but their teacher was, at least, a tomato. For lunch they have tomatoes and tomatoes while reviewing their notes. They feel tomatoes but are determined to complete the course.

Either way, it's important to note that these blank spaces are variable - they can be changed based on inputs. As such, they are a useful tool for exploring variables and inputs.

Demonstrating a toy program

info

A toy program is a small computer program typically used to test a programming language's syntax. It is more complex than "Hello World" but is not intended to be used for anything other than demonstration and practice.

We can use the following program to demonstrate three essential features available in all programming languages:

print("What is your first name?")
first_name = input()
print("What is your last name?")
last_name = input()
print("Hey " + first_name + " " + last_name + "!")

Output

The print() function is a very simple tool, used in this program to output text to the screen. Anything within the parentheses of the print() function will be displayed to the user.

Input

The input() function is used in this program to capture user-provided input. When the program is run it will process each statement in turn, and when it hits the input() function it will wait for the user to press the Enter key. Anything typed in before the Enter key will be taken as input.

By itself, this input() statement would do nothing - it needs to assign the user's input to.. something.

Variables

A variable is somewhere that the program can put data. In this program, anything entered in line 2 is assigned to the first_name variable (in Python, the syntax for a variable is just a word). Anything entered in line 4 is assigned to the last_name variable. Note that in Python, = is the syntax for assigning something, and the thing you're assigning (the output of input()) is on the right of the = sign.

In the final line, we use the + syntax to add together multiple pieces of data - strings of text and variables containing text! Thus, if we assign "Peter" to first_name and "Parker" to last_name then line 5 will print the result of:

"Hey " + "Peter" + " " + "Parker" + "!"

Which is:

Hey Peter Parker!

If both first_name and last_name were assigned the input "Tomato" then we would get:

Hey Tomato Tomato!

Just like the Mad Libs!

info

These concepts are not hard, but they can be weird. Understanding programming involves a lot of lateral thinking. It involves challenging things we thought we understood, and building knowledge that can sometimes feel vague and bewildering. This does not go away - working in tech requires constant development and growth. Good tech workers don't know everything; they do have the persistence, growth mindset and orientation to detail that allows them to solve anything (eventually!).

These are all part of what is referred to as a "developer mindset" in the industry. Good tech workers are not necessarily the quickest to solve a problem; rather, they are the ones that are left when everyone else gives in. Developing a “developer mindset” is as important as technical knowledge - it’s highly valued by employers, and it’s thoroughly tested for in interviews.

Don't worry too much if you don't understand these concepts yet; rather, cultivate a set of behavioural skills and mindsets that allow you to hang on and work through until you do.