🐹 Whack-a-Goph

Small exercises to get you used to reading and writing Go code!

About

Whack-a-Goph is a collection of small Go exercises designed to get you used to reading and writing Go code. Each broken exercise is like a gopher popping up from a hole - fix the code to make the tests pass and "whack" the gopher!

This project is perfect for:

• Go beginners who want hands-on practice
• Developers coming from other languages
• Anyone wanting to brush up on Go fundamentals
• Learning through interactive, immediate feedback

Installation

Prerequisites

• Go 1.21 or later installed on your system
• Basic familiarity with the command line

Install Whack-a-Goph

Option 1: Quick Setup with Make

# Clone the repository
git clone https://github.com/yourusername/whack-a-goph.git
cd whack-a-goph

# Setup everything (install deps + build)
make setup

# See all available commands
make help

Option 2: Manual Setup

# Clone the repository
git clone https://github.com/yourusername/whack-a-goph.git
cd whack-a-goph

# Install dependencies
go mod tidy

# Build the binary
go build -o whack-a-goph .

# Test that it works
./whack-a-goph

Quick Start

Option 1: Using Make Commands (Handles everything)

# See all exercises and their status
make list

# Start with the first exercise
make next

# Run a specific exercise
make run EXERCISE=hello

# Get a hint for an exercise
make hint EXERCISE=hello

# Watch mode - automatically runs tests when you save changes
make watch EXERCISE=hello

# Reset a specific exercise
make reset EXERCISE=hello

# Reset ALL progress (start completely fresh)
make reset-all

Option 2: Using Local Binary (Simple)

# Use the local binary with ./ prefix
./whack-a-goph list
./whack-a-goph next
./whack-a-goph run hello
./whack-a-goph hint hello
./whack-a-goph watch hello

Option 3: Global Installation (No ./ needed)

# Install globally (optional - modifies your PATH)
make install
# or: go install .

# Then use without ./ prefix
whack-a-goph list
whack-a-goph next
whack-a-goph run hello

Choose your preference: Use make commands for convenience, ./whack-a-goph for simplicity, or install globally if you don't mind adding to your PATH.

How It Works

1. List exercises: See all available exercises and your progress
2. Pick an exercise: Each exercise is a broken Go program in the exercises/ directory
3. Fix the code: Edit the .go files to make the tests pass
4. Run tests: Use ./whack-a-goph run <name> or ./whack-a-goph next to test your solution
5. Get feedback: See immediate results with helpful error messages and hints
6. Progress tracking: Your progress is automatically saved

Exercise Topics

• Basics - Hello world, variables, and basic types
• Functions - Function definitions, parameters, and return values
• Control Flow - If statements, loops, and conditional logic
• Structs - Defining structs and methods
• Collections - Slices, arrays, and maps
• Interfaces - Interface definitions and implementations
• Concurrency - Goroutines and channels

Commands

• ./whack-a-goph - Show welcome message and basic usage
• ./whack-a-goph list - List all exercises and their completion status
• ./whack-a-goph run <exercise> - Run a specific exercise
• ./whack-a-goph next - Run the next pending exercise
• ./whack-a-goph watch [exercise] - Watch mode for automatic testing
• ./whack-a-goph hint <exercise> - Get a hint for an exercise
• ./whack-a-goph reset <exercise> - Reset progress for an exercise
• ./whack-a-goph help - Show detailed help information

Note: Commands shown use local binary. Remove ./ if you've installed globally.

Example Session

$ ./whack-a-goph list
🐹  WHACK-A-GOPH!  🐹

🐹 Exercise List
────────────────────────────────────────────────────────────
hello           🕳️  HOLE Get started with a simple hello function
basics          🕳️  HOLE Learn about variables and basic types
functions       🕳️  HOLE Write functions with parameters and return values
...

$ ./whack-a-goph next
🐹 Next exercise: hello
Description: Get started with a simple hello function
File: exercises/01_hello/hello.go

         🐹 *WHOOPS!*

✗ Exercise failed!

Test output:
--- FAIL: TestHello (0.00s)
    hello_test.go:8: Hello() = ""; want "Hello, Gopher!"

💡 Hint: Return the string 'Hello, Gopher!' from the Hello() function

# Edit exercises/01_hello/hello.go to fix the function...

$ ./whack-a-goph next
🐹 Next exercise: hello
Description: Get started with a simple hello function
File: exercises/01_hello/hello.go

         🐹 *WHACKED!*

✓ Exercise passed! 🎉

Progress Tracking

Your progress is automatically saved in .whack-a-goph-progress.json. This file tracks which exercises you've completed, so you can continue where you left off.

Watch Mode

Watch mode is perfect for iterative development:

./whack-a-goph watch hello

This will:

• Run the exercise immediately
• Watch the file for changes
• Automatically re-run tests when you save
• Show live feedback as you work

Press Ctrl+C to exit watch mode.