Learning Unsung Gotchas of Go - Rashmi Nagpal

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Learning Unsung Gotchas in Go Gopher Artwork by Ashley McNamara Rashmi Nagpal Software Engineering Intern, LoopUp GopherCon Russia

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Range iterator returns “two values”

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Defer doesn't work for code blocks, only for the whole function

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Same Address for Different Zero-sized Variables

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Iterating through map using “for range”

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WaitGroup allows the goroutines to cleanly exit before exiting the main program

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Read and Write Operation Reordering

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Unmarshalling JSON numbers into interface values

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Recovering from Panic

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Map is a reference

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Data race condition

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For loop iterators can be reused in go routine

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Defer calls are executed in LIFO manner

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Not to use More() to check if there are remaining JSON objects in a stream

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Non-ASCII punctuation characters aren't supported in struct tags

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Fork-join model should be handled carefully

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Deadlock!

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Bibliography Resources 1. Documentation - The Go Programming Language 2. A Go Gotcha: When Closures and Goroutines Collide 3. Darker Corners of Go – Rytis Biel 4. kstenerud/go-gotchas: Common gotchas with golang and how to work around them Visuals 1. ashleymcnamara/gophers: Gopher Artwork by Ashley McNamara