structs

Golang structs

Package structs implements simple functions to manipulate structs in Golang.

Get it

go get github.com/PumpkinSeed/structs

Contains

Contains reports whether value is within struct

package main

import "github.com/PumpkinSeed/structs"

type Tst struct {
    TestString  string
    TestFloat32 float32
    TestFloat64 float64
}

func main() {
    tst := Tst{
        TestString:  "test",
        TestFloat32: 13.444,
        TestFloat64: 16.444,
    }

    result := structs.Contains(tst, float64(16.444)) // true
    result = structs.Contains(tst, float32(13.444)) // true
}

Benchmark

BenchmarkContains-4   	 3000000	       492 ns/op

Compare

Compare returns a boolean comparing two struct

package main

import "github.com/PumpkinSeed/structs"

type TstA struct {
	TestInt   int
	TestInt8  int8
	TestInt16 int16
}

type TstB struct {
	TestInt   int
	TestInt8  int8
	TestInt16 int16
}

func main() {
    tstA := TstA{
        TestInt:   12,
	    TestInt8:  42,
	    TestInt16: 55,
    }

    tstB := TstB{
        TestInt:   12,
	    TestInt8:  42,
	    TestInt16: 55,
    }

    result := structs.Compare(testStructA, testStructB) // true
}

Benchmark

BenchmarkCompareEqual-4      	 5000000	       379 ns/op
BenchmarkCompareNotEqual-4   	 5000000	       372 ns/op

Index

Index returns the index of the first instance of the value in struct

package main

import "github.com/PumpkinSeed/structs"

type Tst struct {
    TestInt     int
	TestInt8    int8
	TestInt16   int16
	TestInt32   int32
	TestInt64   int64
	TestString  string
	TestBool    bool
	TestFloat32 float32
	TestFloat64 float64
}

func main() {
    tst := Tst{
        TestInt:     12,
		TestInt8:    42,
		TestInt16:   55,
		TestInt32:   33,
		TestInt64:   78,
		TestString:  "test",
		TestBool:    false,
		TestFloat32: 13.444,
		TestFloat64: 16.444,
    }

    result := structs.Index(testStruct, "test") // 5
}

Benchmark

BenchmarkIndex-4             	 5000000	       242 ns/op

FieldNameByValue

FieldNameByValue returns the field's name of the first instance of the value in struct

package main

import "github.com/PumpkinSeed/structs"

type Tst struct {
    TestInt     int
	TestInt8    int8
	TestInt16   int16
	TestInt32   int32
	TestInt64   int64
	TestString  string
	TestBool    bool
	TestFloat32 float32
	TestFloat64 float64
}

func main() {
    tst := Tst{
        TestInt:     12,
		TestInt8:    42,
		TestInt16:   55,
		TestInt32:   33,
		TestInt64:   78,
		TestString:  "test",
		TestBool:    false,
		TestFloat32: 13.444,
		TestFloat64: 16.444,
    }

    result := structs.FieldNameByValue(testStruct, "test") // TestString
}

Benchmark

BenchmarkFieldNameByValue-4   	 5000000	       293 ns/op

Map

The second parameter is a function, apply the function on each field on the struct, or on the condition determined in the third argument

package main

import "github.com/PumpkinSeed/structs"

type Tst struct {
	Username string
	Title    string
	Content  string
}

func main() {
    tst := Tst{
		Username: "PumpkinSeed",
		Title:    "Test title",
		Content:  "Test content",
	}

    result, err := structs.Map(&ts, func(v reflect.Value) error {
		if v.Type() == stringType {
			v.SetString(strings.ToLower(v.String()))
		}
		return nil
	})
}

Benchmark

BenchmarkMap-4                	 5000000	       268 ns/op

Replace

Replace returns a copy of the struct with the first non-overlapping instance of old replaced by new, the last param (n) is the limit, if n < 0, there is no limit on the number of replacements

package main

import "github.com/PumpkinSeed/structs"

type Tst struct {
    TestInt     int
	TestInt8    int8
	TestInt16   int16
	TestInt32   int32
	TestInt64   int64
	TestString1    string
	TestString2    string
	TestString3    string
	TestString4    string
	TestBool    bool
	TestFloat32 float32
	TestFloat64 float64
}

func main() {
    tst := Tst{
        TestInt:     12,
		TestInt8:    42,
		TestInt16:   55,
		TestInt32:   33,
		TestInt64:   78,
		TestString1:    "test",
		TestString2:    "test",
		TestString3:    "test",
		TestString4:    "test",
		TestBool:    false,
		TestFloat32: 13.444,
		TestFloat64: 16.444,
    }

    result, err := structs.Replace(&ts, "test", "new", 2)
}

Benchmark

BenchmarkReplace-4            	 2000000	       655 ns/op

ToDo

• Upgrade GoDoc
• Implement Map