util

func AddUnique ¶

func AddUnique[T comparable](s []T, v T) []T

func AppendStrInt ¶

func AppendStrInt(sb *strings.Builder, x int)

func AppendStrInt32 ¶

func AppendStrInt32(sb *strings.Builder, x int32)

func AppendStrInt64 ¶

func AppendStrInt64(sb *strings.Builder, x int64)

func AppendStrUInt ¶

func AppendStrUInt(sb *strings.Builder, x uint)

func AppendStrUInt32 ¶

func AppendStrUInt32(sb *strings.Builder, x uint32)

func AppendStrUInt64 ¶

func AppendStrUInt64(sb *strings.Builder, x uint64)

func ArrayToMap ¶

func ArrayToMap[V any](s []V) map[int]V

ArrayToMap converts a slice to a map with the index as the key.

func ArrayToMapFunc ¶ added in v0.20.19

func ArrayToMapFunc[K comparable, V any](s []V, fn func(V) K) map[K]V

func ArrayToSet ¶

func ArrayToSet[T comparable](s []T) map[T]struct{}

ArrayToSet converts a slice to a set (i.e. map).

func B2S ¶

func B2S(bts []byte) string

B2S is alias for ByteToStr.

func ByteToStr ¶

func ByteToStr(bts []byte) string

ByteToStr converts byte slice to a string without memory allocation. Note it may break if string and/or slice header will change in the future go versions.

func CPUTicks ¶

func CPUTicks() int64

CPUTicks is a faster alternative to NanoTime to measure time duration.

func Cast ¶

func Cast[T any](val any) T

Cast Converts any type to a given type. If conversion fails, it returns the zero value of the given type.

func CastJSON ¶

func CastJSON[T any](val any) T

CastJSON Converts any type to a given type based on their json representation. It partially fills the target in case they are not directly compatible.

func CloneBytes ¶

func CloneBytes(b []byte) []byte

func CloneStr ¶

func CloneStr(s string) string

func Coalesce ¶

func Coalesce[T comparable](in ...T) T

Coalesce returns the first non-zero value from the input list.

func Contains ¶

func Contains[T comparable](s []T, v T) bool

func ContainsAll ¶

func ContainsAll[T comparable](s []T, v []T) bool

func ContainsAny ¶

func ContainsAny[T comparable](s []T, v []T) bool

func CopyFile ¶

func CopyFile(srcFile, dstFile string) error

func CopyFileWithBuffer ¶

func CopyFileWithBuffer(srcFile, dstFile string, buf []byte) error

func DynCast ¶

func DynCast[DST, SRC any](src SRC, mappingPair ...string) DST

func DynCastOption ¶

func DynCastOption[DST, SRC any](
	src SRC,
	converters []TypeConverter,
	mappingPair ...string,
) DST

func F32ToStr ¶

func F32ToStr(x float32) string

func F64ToStr ¶

func F64ToStr(x float64) string

func FastRand ¶

func FastRand() uint32

FastRand is a fast thread local random function.

func Filter ¶

func Filter[T any](tt []T, match func(src T) bool) []T

Filter returns a new slice containing only the elements in tt for which the match function returns true.

	type User struct {
		Name string
		Age  int
		Active bool
}

var users = []User{
	{"Tom", 20, true},
	{"Jack", 22, false},
	{"Mary", 18, true},
}

var activeUsers = qkit.Filter(users, func(u User) bool {
	return u.Active
})

fmt.Println(activeUsers)

Playground: https://go.dev/play/p/70YOKRs79OF

func First ¶

func First[K, V comparable](in map[K]V, keys ...K) (V, bool)

First returns the first value found in the map for the given keys.

func FirstOr ¶

func FirstOr[K, V comparable](def V, in map[K]V, keys ...K) V

func Float32ToStr ¶

func Float32ToStr(x float32) string

func Float64ToStr ¶

func Float64ToStr(x float64) string

func ForEach ¶

func ForEach[V any](in []V, fn func(*V))

func FromJSON ¶

func FromJSON[T any](bytes []byte) T

FromJSON Converts a byte array to a given type.

func GetExecDir ¶

func GetExecDir() string

func GetExecName ¶

func GetExecName() string

func Int32ToStr ¶

func Int32ToStr(x int32) string

func Int64ToStr ¶

func Int64ToStr(x int64) string

func IntToStr ¶

func IntToStr(x int) string

func Map ¶

func Map[S, D any](ss []S, transformer func(src S) D) []D

Map applies the transformer function to each element of the slice ss. The result is a slice of the same length as ss, where the kth element is transformer(ss[k]).

type User struct {
	Name string
	Age  int
}

var users = []User{
	{"Tom", 20},
	{"Jack", 22},
	{"Mary", 18},
}

var names = qkit.Map(users, func(u User) string {
	return u.Name
})

fmt.Println(names)

Playground: https://go.dev/play/p/wKIa32-rMDn

func MapKeysToArray ¶

func MapKeysToArray[K comparable, V any](s map[K]V) []K

MapKeysToArray converts a map's keys to a slice.

func MapToArray ¶

func MapToArray[K comparable, V any](s map[K]V) []V

MapToArray converts a map's values to a slice.

func MapToArrayFunc ¶

func MapToArrayFunc[K comparable, V any, T any](s map[K]V, fn func(K, V) T) []T

MapToArrayFunc converts a map's values to a slice using the given function.

func Must ¶

func Must[T any](src T, err error) T

Must panics if err is not nil.

func MustSha256 ¶

func MustSha256(in, out []byte) []byte

func MustSha512 ¶

func MustSha512(in, out []byte) []byte

MustSha512 is Sha512 but it panics if any error happens.

func NanoTime ¶

func NanoTime() int64

NanoTime returns the current time in nanoseconds from a monotonic clock.

func Ok ¶

func Ok[T any](v T, _ error) T

Ok returns the value and ignores the error.

func OkOr ¶

func OkOr[T any](v T, err error, fallback T) T

OkOr returns the value if err is nil, otherwise returns the fallback value.

func Paginate ¶

func Paginate[T any](arr []T, pageSize int, fn func(start, end int) error) error

Paginate will call the given function with start and end indexes for a slice of the given size.

type User struct {
	Name string
	Age  int
}

var users = []User{
	{"Tom", 20},
	{"Jack", 22},
	{"Mary", 18},
	{"Tommy", 20},
	{"Lin", 22},
}

qkit.Paginate(users, 2, func(start, end int) error {
	fmt.Println(users[start:end])
	return nil
})

Playground: https://go.dev/play/p/aDiVJEKjgwW

func PtrVal ¶

func PtrVal[T any](src *T) T

PtrVal returns the value of the pointer src. It is a dereference operation.

func RandomDigit ¶

func RandomDigit(n int) string

RandomDigit generates a pseudo-random string with length 'n' which characters are only digits (0-9).

func RandomID ¶

func RandomID(n int) string

RandomID generates a pseudo-random string with length 'n' which characters are alphanumerics.

func RandomIDs ¶

func RandomIDs(n ...int) []string

func RandomInt ¶

func RandomInt(n int) (x int)

func RandomInt32 ¶

func RandomInt32(n int32) (x int32)

RandomInt32 produces a pseudo-random 31bit number, if n == 0 there will be no limit otherwise the output will be smaller than n.

func RandomInt64 ¶

func RandomInt64(n int64) (x int64)

RandomInt64 produces a pseudo-random 63bit number, if n == 0 there will be no limit otherwise the output will be smaller than n.

func RandomUint64 ¶

func RandomUint64(n uint64) (x uint64)

RandomUint64 produces a pseudo-random unsigned number.

func ReadYamlFile ¶

func ReadYamlFile(filePath string, data any) error

func Reduce ¶

func Reduce[T, R any](reducer func(r R, t T) R, tt []T) R

Reduce [T, R] reduces the slice tt to a single value r using the reducer function. The reducer function takes the current reduced value r and the current slice value t and returns a new reduced value.

type User struct {
	Name string
	Age  int
}

var users = []User{
	{"Tom", 20},
	{"Jack", 22},
	{"Mary", 18},
}

var totalAge = qkit.Reduce(func(r int, u User) int {
	return r + u.Age
}, users)

fmt.Println(totalAge)

Playground: https://go.dev/play/p/gf9evzMIMIK

func S2B ¶

func S2B(str string) []byte

S2B is alias for StrToByte.

func SecureRandomInt63 ¶

func SecureRandomInt63(n int64) (x int64)

SecureRandomInt63 produces a secure pseudo-random 63bit number.

func SecureRandomUint64 ¶

func SecureRandomUint64() (x uint64)

SecureRandomUint64 produces a secure pseudo-random 64bit number.

func Sha256 ¶

func Sha256(in, out []byte) ([]byte, error)

Sha256 appends a 32bytes array which is sha256(in) to out.

func Sha512 ¶

func Sha512(in, out []byte) ([]byte, error)

Sha512 appends a 64bytes array which is sha512(in) to out and returns out.

func StrToByte ¶

func StrToByte(str string) (b []byte)

StrToByte converts string to a byte slice without memory allocation. Note it may break if string and/or slice header will change in the future go versions.

func StrToFloat32 ¶

func StrToFloat32(s string) float32

func StrToFloat64 ¶

func StrToFloat64(s string) float64

func StrToInt ¶

func StrToInt(s string) int

func StrToInt32 ¶

func StrToInt32(s string) int32

func StrToInt64 ¶

func StrToInt64(s string) int64

func StrToUInt ¶

func StrToUInt(s string) uint

func StrToUInt32 ¶

func StrToUInt32(s string) uint32

func StrToUInt64 ¶

func StrToUInt64(s string) uint64

func StrTruncate ¶

func StrTruncate(s string, maxSize int) string

func TimeUnix ¶

func TimeUnix() int64

func TimeUnixAdd ¶

func TimeUnixAdd(unixTime int64, d time.Duration) int64

func TimeUnixSubtract ¶

func TimeUnixSubtract(unixTime int64, d time.Duration) int64

func ToCamel ¶

func ToCamel(s string) string

ToCamel converts a string to CamelCase.

func ToDelimited ¶

func ToDelimited(s string, delimiter uint8) string

ToDelimited converts a string to delimited.snake.case (in this case `delimiter = '.'`).

func ToJSON ¶

func ToJSON(val any) []byte

ToJSON Converts a given value to a byte array.

func ToKebab ¶

func ToKebab(s string) string

ToKebab converts a string to kebab-case.

func ToLowerCamel ¶

func ToLowerCamel(s string) string

ToLowerCamel converts a string to lowerCamelCase.

func ToMap ¶

func ToMap(s any) map[string]any

ToMap Converts any type to a map[string]interface{}.

func ToScreamingDelimited ¶

func ToScreamingDelimited(
	s string,
	delimiter uint8,
	ignore uint8,
	screaming bool,
) string

ToScreamingDelimited converts a string to SCREAMING.DELIMITED.SNAKE.CASE (in this case `delimiter = '.'; screaming = true`) or delimited.snake.case (in this case `delimiter = '.'; screaming = false`).

func ToScreamingKebab ¶

func ToScreamingKebab(s string) string

ToScreamingKebab converts a string to SCREAMING-KEBAB-CASE.

func ToScreamingSnake ¶

func ToScreamingSnake(s string) string

ToScreamingSnake converts a string to SCREAMING_SNAKE_CASE.

func ToSnake ¶

func ToSnake(s string) string

ToSnake converts a string to snake_case.

func ToSnakeWithIgnore ¶

func ToSnakeWithIgnore(s string, ignore uint8) string

func TryCast ¶

func TryCast[T any](v any) T

TryCast tries to cast the input value to the target type. If the cast fails, it returns the zero value of the target type.

func UInt32ToStr ¶

func UInt32ToStr(x uint32) string

func UInt64ToStr ¶

func UInt64ToStr(x uint64) string

func UIntToStr ¶

func UIntToStr(x uint) string

func ValPtr ¶

func ValPtr[T any](src T) *T

ValPtr returns the pointer of the src. It is a reference operation.

func ValPtrOrNil ¶

func ValPtrOrNil[T comparable](src T) *T

ValPtrOrNil returns the pointer of the src if src is not zero value, otherwise nil.

func VisitAll ¶

func VisitAll[VisitorState any](
	initial VisitorState,
	visitors ...func(ctx *VisitorState),
) VisitorState

VisitAll runs all visitors and returns the final state.

func VisitCond ¶

func VisitCond[VisitorState any](
	initial VisitorState,
	cond func(ctx *VisitorState) bool,
	visitors ...func(ctx *VisitorState),
) VisitorState

VisitCond runs all visitors if the condition is true and returns the final state If the condition is false, the visitor will stop and DO NOT run the rest of the visitors. cond function is called before each visitor.

NOTE: `cond` is called before each visitor, hence, it will be run on initial state too.

func VisitStopOnErr ¶

func VisitStopOnErr[VisitorState any](
	initial VisitorState,
	visitors ...func(ctx *VisitorState) error,
) (VisitorState, error)

VisitStopOnErr runs all visitors and returns the final state If any of the visitors returns an error, the visitor will stop and DO NOT run the rest of the visitors. It returns the latest state and the error.

func WriteYamlFile ¶

func WriteYamlFile(filePath string, data any) error