Miki Tebeka - Go Brain Teasers: Exercise Your Mind

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To Sharon, who suffered me in quarantine, and the twenty years before that.

Im grateful for every contribution, from finding bugs to fixing grammar toletting me work in peace.

Here is a list of people who helped; my apologies to anyone I forgot:

• Adi Tebeka for her proofreading and comments.

• Dan Allen for his help in the asciidoctor forums. I used the wonderful asciidoctor to write the initial version of this book.

• Dave Cheney for the foreword.

• David Bordeynik for his comments.

• Egon Elbre who drew all these wonderful gophers and placed them in CC0 license.

• Elad Eyal for proofreading.

• Eliran Bivas for proofreading and comments.

• Jared David for his quote.

• Ran Tavory for his comments.

• Yoni Davidson for his comments.

Im also grateful to Brad Fitzpartick and others who post Go pop quizzes andgave me many ideas for these brain teasers.

The Go programming language is a simple one, but like all other languages, ithas its quirks. This book uses these quirks as a teaching opportunity. Byunderstanding the gaps in your knowledge, youll become better at what you do.

Theres a lot of research showing that people who make mistakes during thelearning process learn better than people who dont. If you use this approachat work when fixing bugs, youll find you enjoy bug hunting more and become abetter developer after each bug you fix.

These teasers will help you avoid mistakes. Some of the teasers are from my ownexperience shipping bugs to production, and some are from others doing the same.

Teasers are fun! We geeks love puzzles and solving them. You can also use theseteasers to impress your coworkers, have knowledge competitions, and becomebetter together.

Many of these brain teasers are from quizzes I gave at conferences andmeetups. Ive found that people highly enjoy them, and they tend to liventhe room.

At the beginning of each chapter, Ill show you a short Go program and askyou to guess the output. The possible answers can be the following:

• Wont compile
• Panic
• Deadlock
• Some output (e.g., [1 2 3] )

Go Version
	Ive used Go version 1.14.1 to run the code; the output might change in future versions.

Before moving on to the answer and the explanation, go ahead and guessthe output. After guessing the output, I encourage you to run the codeand see the output yourself; only then proceed to read the solution andthe explanation. Ive been teaching programming for many years andfound this course of action to be highly effective.