Go Programming Interview Questions - Boolean Type in GoLang скачать в хорошем качестве

Go Programming Interview Questions - Boolean Type in GoLang

Learn everything important about the bool type in Go and how it works in real programs. We start with the basics: the boolean type in Go is called bool and it has only two values, true and false. Its zero value is false, which means an uninitialized bool is automatically false. Then we go deeper into memory and representation. A bool in Go uses 1 byte (8 bits), not 1 bit. Internally, false is stored as 0x00 and true as 0x01. You will also understand why Go uses 1 byte instead of 1 bit and how CPUs are byte-addressable. We cover allowed operations on bool values, including comparison with == and !=, and explain why and are not allowed. You will also learn how comparison operators return boolean values. Logical operators are explained clearly: AND, OR, and NOT. We demonstrate short-circuit behavior and explain operator precedence, including why AND is evaluated before OR. You will understand why Go does not support truthy or falsy values like some other languages. In Go, you must always write explicit comparisons. You cannot use 0, nil, or empty strings directly in if statements. 00:00 Boolean Type Basics in Go 00:47 How Bool is Stored in Memory (1 Byte) 01:43 Comparison Operators Return Booleans 02:03 Logical Operators & Short-Circuit Evaluation 02:54 Operator Precedence: AND vs OR 03:13 No Truthy/Falsy Values in Go 03:44 No Direct Casting Between Bool and Int 04:14 Struct Field Ordering & Memory Padding 04:57 Printing Booleans (%t Format Verb) 05:34 Parsing Booleans from Strings (strconv) 06:24 JSON Encoding/Decoding Booleans 07:04 Optional Booleans with *bool Pointers 07:58 Atomic Bool for Safe Goroutine Access 08:40 Custom Boolean Types (Type Safety) 09:32 Booleans in Interfaces & Reflection 10:12 Toggling Boolean Values (! Operator) 10:40 Conditional Assignment (No Ternary Operator) 11:16 All/Any Helper Functions for Slices 11:56 Data Races with Shared Booleans 12:42 Bit Manipulation for Efficient Flags 13:29 Handling NULL Booleans in Databases (sql.NullBool) 14:17 Nullable Booleans in Protocol Buffers/gRPC 15:06 Compiler Optimizations for Boolean Logic We also explain why Go does not allow direct casting between bool and int, and how to convert manually using logic. Struct field alignment and memory padding are covered in detail. You will see why the order of bool fields in a struct matters and how bad ordering can waste memory. Printing and formatting booleans using the fmt package is demonstrated, including the correct use of %t and %v. String conversion is explained using the strconv package. You will learn how strconv.ParseBool accepts values like true, false, 1, 0, T, and F, and how strconv.FormatBool converts a bool back to a string. JSON encoding and decoding with the encoding/json package is covered. You will learn how omitempty works with bool fields, how missing fields default to false, and why JSON only accepts lowercase true and false. We explain how to represent optional boolean fields using *bool pointers for three-state logic: nil, true, and false. Concurrency is an important topic. You will learn why a normal bool is not safe between goroutines and how to use atomic.Bool from sync/atomic (available since Go 1.19) to prevent data races. Custom boolean types are explained, including how to add methods and why explicit conversion is required between custom types and built-in bool. We also cover working with bool inside interfaces and reflection, including type assertions, type switches, and reflect.Kind checks. Practical patterns are included: Toggling a bool using the NOT operator Conditional assignment without a ternary operator Implementing all and any logic for slices of booleans Advanced topics include: Using bit manipulation instead of many bool fields Handling NULL booleans in databases using sql.NullBool Nullable booleans in Protocol Buffers with google.protobuf.BoolValue How the Go compiler optimizes boolean expressions and avoids unnecessary branches This video gives you a complete, practical, and in-depth reference for working with boolean values in Go, from basic syntax to advanced performance and concurrency topics.