typeutil

Documentation

Overview

Package typeutil contains a collection of type-related generic utility functions.

This package provides a set of utility functions and definitions for working with generic types in Go.

Index

• func BoolToInt(b bool) int
• func IsNil(v any) bool
• func IsZero[T any](v T) bool
• func Pointer[T any](v T) *T
• func Value[T any](p *T) T
• func Zero[T any](_ T) T
• type Float
• type Int
• type Number
• type Ordered
• type UInt

Examples

• IsNil
• IsZero
• Pointer
• Value
• Zero

Functions

func BoolToInt

func BoolToInt(b bool) int

BoolToInt converts a boolean value to an integer.

NOTE: this is currently the fastest implementation as it will be optimized by the compiler with a MOVBLZX instruction. Ref.:

• https://0x0f.me/blog/golang-compiler-optimization/
• https://github.com/golang/go/issues/6011

func IsNil

func IsNil(v any) bool

IsNil returns true if the input value is nil.

Example

package main

import (
	"fmt"

	"github.com/Vonage/gosrvlib/pkg/typeutil"
)

func main() {
	var nilChan chan int

	v := typeutil.IsNil(nilChan)
	fmt.Println(v)

}

Output:

true

func IsZero

func IsZero[T any](v T) bool

IsZero returns true if the input value is equal to the zero instance (e.g. empty string, 0 int, nil pointer).

Example

package main

import (
	"fmt"

	"github.com/Vonage/gosrvlib/pkg/typeutil"
)

func main() {
	var zeroInt int

	v := typeutil.IsZero(zeroInt)
	fmt.Println(v)

}

Output:

true

func Pointer

func Pointer[T any](v T) *T

Pointer returns the address of v.

Example

package main

import (
	"fmt"

	"github.com/Vonage/gosrvlib/pkg/typeutil"
)

func main() {
	v := 5

	p := typeutil.Pointer(v)
	fmt.Println(p)
}

func Value

func Value[T any](p *T) T

Value returns the value of the provided pointer or the type default (zero value) if nil.

Example

package main

import (
	"fmt"

	"github.com/Vonage/gosrvlib/pkg/typeutil"
)

func main() {
	num := 5
	p := &num

	v := typeutil.Value(p)
	fmt.Println(v)

}

Output:

5

func Zero

func Zero[T any](_ T) T

Zero returns the zero instance (e.g. empty string, 0 int, nil pointer).

Example

package main

import (
	"fmt"

	"github.com/Vonage/gosrvlib/pkg/typeutil"
)

func main() {
	num := 5

	v := typeutil.Zero(num)
	fmt.Println(v)

}

Output:

0

Types

type Float

type Float interface {
	~float32 | ~float64
}

Float is a constraint for float types.

type Int

type Int interface {
	~int | ~int8 | ~int16 | ~int32 | ~int64
}

Int is a constraint for signed integer types.

type Number

type Number interface {
	Int | UInt | Float
}

Number is a constraint for all integer and float numbers.

type Ordered

type Ordered interface {
	Number | ~string
}

Ordered is a constraint that permits any ordered type: any type that supports the operators < <= >= >.

type UInt

type UInt interface {
	~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
}

UInt is a constraint for unsigned integer types.