What is the basic knowledge of Go language

This article will explain in detail what the basic knowledge of Go language is, which the editor thinks is very practical, so I share it for you as a reference. I hope you can get something after reading this article.

1. The basic structure of Go program

The following is the basic structure of a Go program, including (package declaration, introduction package, function, etc.)

Package main

Import "fmt"

Func main () {

Fmt.Println ("Hello, World!")}

two。 Data type

Go built-in basic data types include basic data types and advanced data types

1. Basic data type

Boolean type (bool)

Numerical type

Integer type (byte,rune,int/uint,int8/uint8,int16/uint16,int32/uint32,int64/uint64)

Floating point type (float32,float64)

Plural type (complex64,complex128)

String type

String Go strings are concatenated by a single byte. Use UTF-8 encoding to identify Unicode text.

two。 Advanced data type

Array (array)

Slice (slice)

Dictionary (map)

Channel (channel)

Function (function)

Structure (function)

Interface (interface)

Pointer (* Xxx,Pointer,uintptr)

If divided according to the underlying structure, the value types include (all basic data types, arrays, structures), and the reference types include (slice,map,channel,function,interface, pointer)

3. Variable & constant

1. The variable name consists of letters, numbers, and underscores, in which the first letter cannot be a number, for example: var name string

two。 Statement

a. Specify the variable type, and if no value is assigned after declaration, use the default value.

Var name string

Name = "Li Si"

b. Determine the variable type according to the value.

Var name = "Li Si"

c. Short form, omitting var, note

Age: = 10

Be careful

(: =) is the preferred form for using variables

(: =) can only be used in the body of a function, not in the declaration and assignment of global variables.

(: =) the variable on the left should not have been declared, otherwise it will cause a compilation error.

3. Constant data types can only be Boolean, numeric (integer, floating-point, and plural), and string.

1. Constant declaration: const b string = "abc"

2. Iota, special constant

Const (

A = iota

B

C

)

1. Represents a continuous, untyped integer constant

two。 In constant declaration statements that begin with const

3. Increment once without assigning a constant, starting at 0

4. Once you cross a constant declaration statement that starts with const, it returns to 0.

4. Operator

1. Arithmetic operator, a + b, including (+, -, *, /,%, +, -)

two。 Relational operator, which returns True or False, a = = b, including (= =,! =, >, =