table-of-contents-eng

Table of Contents 1

Introduction 5

Language Mechanics 6

Syntax 6

Variable 6

Built-in types 6

Zero value concept 6

Declare and initialize 7

Conversion vs casting 8

Struct 8

Declare and initialize 8

Name type vs anonymous type 10

Pointer 11

Everything is about pass by value 11

Pass by value 11

Escape analysis 12

Function 15

Constant 17

Declare and initialize 17

iota 19

Data Structures 20

Array 20

CPU Cache 20

Translation Lookaside Buffer 21

Declare and initialize 21

What is the cost? 22

Iterate over the array of strings 23

Different type arrays 24

Contiguous memory allocations 24

Slice 25

Declare and initialize 25

Length vs Capacity 25

Reference type 26

Idea of appending: making slice a dynamic data structure 27

Slice of slice 30

Copy a slice 31

Slice and reference 32

UTF-8 33

Map 34

Declare and initialize 35

Map literals 35

Delete key 36

Find key 36

Map key restrictions 36

Decoupling 37

Method 37

Value and Pointer Receiver Call 37

Value and Pointer Semantics 39

Methods are just functions 43

Interface 46

Valueless type 46

Interface via pointer receiver 50

Slice of interface 53

Embedding 55

Declaring fields, NOT Embedding 55

Embedding types 56

Embedded type and Interface 57

Outer and inner type implementing the same interface 58

Exporting 60

Guideline 60

Exported identifier 60

Accessing a value of an unexported identifier 61

Unexported fields from an exported struct 62

Exported types with embedded unexported types 63

Software Design 65

Composition 65

Grouping types 65

Grouping By State 65

Grouping By Behavior 67

Decoupling 70

Struct Composition 70

Decoupling With Interface 74

Interface Composition 79

Decoupling With Interface Composition 84

Conversion 89

Interface Conversions 89

Type assertion 91

Runtime Type Assertion 92

Interface Pollution 94

Remove Interface Pollution 96

Mocking 98

Package To Mock 98

Client 100

Error Handling 101

Default error values 101

Error variables 103

Type as context 105

Behavior as context 107

Finding the bug 110

Wrapping Errors 111

Concurrency 114

Mechanics 114

Goroutine 114

Language Mechanics 121

Sequence 123

Goroutine time slicing 124

Goroutines and parallelism 126

Data race 128

Race Detection 128

Atomic Functions 131

Mutexes 133

Read/Write Mutex 135

Channel 139

Language Mechanics 139

Unbuffered channel: Signaling with data 141

Unbuffered channel: Double signal 143

Unbuffered channel: select and receive 144

Unbuffered channel: select and send 145

Buffered channel: Select and drop 146

Unbuffered channel (Tennis match) 148

Unbuffered channel (Replay race) 150

Buffered channel: Fan Out 153

Select 157

Patterns 164

Context 164

Store and retrieve values from a context 164

WithCancel 166

WithDeadline 168

WithTimeout 169

Request/Response 171

Testing and Profiling 173

Testing 173

Basic Unit Test 173

Table Test 176

Sub Test 177

Web Server 181

Mock Server 187

Benchmarking 191

Basic Benchmark 191

Sub Benchmark 192

Profiling 193

Stack Trace 193

Review Stack Trace 193

Packing 195

GODEBUG 196

Memory Tracing 196

Keep in touch 199