go/syntax.in.go

// A line comment.

/*
A general comment.
*/

// Keywords

    break        default      func         interface    select
    case         defer        go           map          struct
    chan         else         goto         package      switch
    const        fallthrough  if           range        type
    continue     for          import       return       var

// Operators, delimiters and special tokens

    +    &     +=    &=     &&    ==    !=    (    )
    -    |     -=    |=     ||    <     <=    [    ]
    *    ^     *=    ^=     <-    >     >=    {    }
    /    <<    /=    <<=    ++    =     :=    ,    ;
    %    >>    %=    >>=    --    !     ...   .    :
         &^          &^=

// Integer literals

    42
    0600
    0xBadFace
    170141183460469231731687303715884105727

// Floating-point literals

    0.
    72.40
    072.40
    2.71828
    1.e+0
    6.67428e-11
    1E6
    .25
    .12345E+5

// Imaginary literals

    0i
    011i
    0.i
    2.71828i
    1.e+0i
    6.67428e-11i
    1E6i
    .25i
    .12345E+5i

// Character literals

    'a'
    'ä'
    '本'
    '\t'
    '\000'
    '\007'
    '\377'
    '\x07'
    '\xff'
    '\u12e4'
    '\U00101234'

// String literals

    `abc`
    `\n
    \n`
    "\n"
    ""
    "Hello, world!\n"
    "日本語"
    "\u65e5本\U00008a9e"
    "\xff\u00FF"
    "\uD800"       // illegal: surrogate half
    "\U00110000"   // illegal: invalid Unicode code point
    "\z"           // illegal

// Predeclared identifiers

    // Types:
    bool byte complex64 complex128 error float32 float64
    int int8 int16 int32 int64 rune string
    uint uint8 uint16 uint32 uint64 uintptr

    // Constants:
    true false iota

    // Zero value:
    nil

    // Functions:
    append cap close complex copy delete imag len
    make new panic print println real recover

// Types

    type T1 string
    type T2 T1
    type T3 []T1
    type T4 T3

// Array types

    [32]byte
    [2*N] struct { x, y int32 }
    [1000]*float64
    [3][5]int
    [2][2][2]float64

// Struct types

    struct {}

    struct {
        x, y int
        u float32
        _ float32
        A *[]int
        F func()
    }

    struct {
        T1
        *T2
        P.T3
        *P.T4
        x, y int
    }

    struct {
        T
        *T
        *P.T
    }

    struct {
        microsec  uint64 "field 1"
        serverIP6 uint64 "field 2"
        process   string "field 3"
    }

// Function types

    func()
    func(x int) int
    func(a, _ int, z float32) bool
    func(a, b int, z float32) (bool)
    func(prefix string, values ...int)
    func(a, b int, z float64, opt ...interface{}) (success bool)
    func(int, int, float64) (float64, *[]int)
    func(n int) func(p *T)

// Interface types

    interface {
        Read(b Buffer) bool
        Write(b Buffer) bool
        Close()
    }

    type Lock interface {
        Lock()
        Unlock()
    }

// Channel types

    chan T
    chan<- float64
    <-chan int

    chan<- chan int
    chan<- <-chan int
    <-chan <-chan int
    chan (<-chan int)