Go language Learning

This is a creation in Article, where the information may have evolved or changed.

Installation of 1.go languages

The blogger's environment is ubuntu14.04, so the installation of the Go language environment is directly used

sudo apt-get install Golang

After the installation is complete

2.hello World

The code is as follows

/* Hello.go */package Mainimport "FMT" Func Main () {FMT. Println ("hello,world!")}

Note Println Method P is uppercase

Then run the terminal compile

Go Run hello.go

or use the build command to build the executable file

Go Build

Some grammatical knowledge of 3.go

Go each individual statement does not require a special separator line, default to the line delimiter as the statement delimiter

Keyword var tag variable, const TAG constant

Declaration of a variable

package mainimport  "FMT" Func main () {    const  ( a  =  0 ; b )     const ( c = 0 ; d = 1  )     const e  = 3    const f int8 The  = 4    /*  keyword iota represents a continuous, untyped integer constant, and iota defaults to 0 and increments incrementally. Each time the iota appears, its value is 0 */    const  ( g = iota ; h ; i  )     const j = iota    var k int =  1    var  l int    l = 2     /*  defaults to Int */    var ( m = 42949672960 ; n  = 4294967296 )     var ( o int8 = 1 ; p =  1 )     fmt. Println (A)     fmt. Println (b)     fmt. Println (c)     fmt. Println (d)     fmt. Println (e)     fmt. Println (f)     fmt. Println (g)     fmt. Println (h)     fmt. Println (i)     fmt. Println (j)     fmt. Println (k)     fmt. Println (L)     fmt. Println (m)     fmt. PRINTLN (n)     fmt. Println (o)     fmt. Println (P)}

The data type of GO is probably

boolean Types They are Boolean types, and it consists of two predefined constants: (a) True (b) False

Numeric Types They are arithmetic types that represent integer types or B. The entire program floating-point value

string Types: A String type represents a group string value. Its value is a sequence of bytes. The string is created at once by a stable type, which is not possible to change the contents of a string. The pre-declared string type is a string

Derived types: They include: (a) pointer type, (b) array type, (c) struct type, (d) union type and (e) function type (f) slice class (g) function type (h) interface type (i) map type (j) Pipe type

Boolean Types

BOOL type, variable value is only True,false

Assignment of 0, 1 is not supported

Package Mainimport "FMT" Func Main () {var a bool A = True FMT. Println (a) A = False fmt. Println (A)}

Output results

Numeric Types

Signed Integral type int8 int16 int32 int64

Unsigned integral type uint8 uint16 UInt32 UInt64

Floating point float32 float64

Retelling complex64 complex128

Other

byte identical to Uint8

Rune Identical to Int32

UINT 32-bit or 64-bit

int size is the same as uint

package mainimport  "FMT" Func main () {    fmt. Println (10/3)     fmt. Println (10E5)     fmt. Println (0x5)     var a int8    a = 12     fmt. Println (a)     var b int16    b = 12     fmt. Println (b)     /*  signed, so when C is greater than 127 or less than 127 it will error  */         var c int8        c = 127         fmt. Println (c)     /*  unsigned, so when D is greater than 255 or less than 0 the error will be  */    var d  uint8    d = 255    fmt. Println (d)     var e int    e = 4294967297     fmt. Println (e)     var f float32    f = 3.2     Fmt. Println (f)     var g complex64    g = 3+2i     fmt. Println (g)}

String Types

The smallest unit of the constituent string is the character, the smallest unit stored is the byte, and the string itself does not support modification.

Package Mainimport "FMT" Func Main () {/* default is int */var a = ' a ' var b = "abc" var c string = "abc" FMT. Println (a) fmt. Println (b) fmt. Println (c)}