grand

Documentation

Overview

Package grand provides high performance random bytes/number/string generation functionality.

Index

• func B(n int) []byte
• func Digits(n int) string
• func Intn(max int) int
• func Letters(n int) string
• func Meet(num, total int) bool
• func MeetProb(prob float32) bool
• func N(min, max int) int
• func Perm(n int) []int
• func S(n int, symbols ...bool) string
• func Str(s string, n int) string
• func Symbols(n int) string

Functions

func B

func B(n int) []byte

B retrieves and returns random bytes of given length <n>.

func Digits

func Digits(n int) string

Digits returns a random string which contains only digits, and its length is <n>.

func Intn

func Intn(max int) int

Intn returns a int number which is between 0 and max: [0, max).

Note that: 1. The <max> can only be greater than 0, or else it returns <max> directly; 2. The result is greater than or equal to 0, but less than <max>; 3. The result number is 32bit and less than math.MaxUint32.

func Letters

func Letters(n int) string

Letters returns a random string which contains only letters, and its length is <n>.

func Meet

func Meet(num, total int) bool

Meet randomly calculate whether the given probability <num>/<total> is met.

func MeetProb

func MeetProb(prob float32) bool

MeetProb randomly calculate whether the given probability is met.

func N

func N(min, max int) int

N returns a random int between min and max: [min, max]. The <min> and <max> also support negative numbers.

func Perm

func Perm(n int) []int

Perm returns, as a slice of n int numbers, a pseudo-random permutation of the integers [0,n). TODO performance improving for large slice producing.

func S

func S(n int, symbols ...bool) string

S returns a random string which contains digits and letters, and its length is <n>. The optional parameter <symbols> specifies whether the result could contain symbols, which is false in default.

func Str

func Str(s string, n int) string

Str randomly picks and returns <n> count of chars from given string <s>. It also supports unicode string like Chinese/Russian/Japanese, etc.

func Symbols

func Symbols(n int) string

Symbols returns a random string which contains only symbols, and its length is <n>.