opcotech/elemo

package convert

import (
    "errors"

    "github.com/goccy/go-json"
)

var (
    ErrMarshal   = errors.New("could not marshal value")   // value could not be marshaled
    ErrUnmarshal = errors.New("could not unmarshal value") // value could not be unmarshaled
)

// ToPointer converts any value to a pointer, but nil.
//
// If the value is nil, it panics.
func ToPointer[T any](src T) *T {
    return &src
}

// AnyToAny converts any value to any type that can be converted using
// json.Marshal and json.Unmarshal. If the output is set to nil, the
// function converts to nil.
func AnyToAny(input any, output any) error {
    if output == nil {
        return nil
    }

    var err error

    b, err := json.Marshal(&input)
    if err != nil {
        return errors.Join(ErrMarshal, err)
    }

    if err = json.Unmarshal(b, output); err != nil {
        return errors.Join(ErrUnmarshal, err)
    }

    return nil
}

// MustAnyToAny converts any value to any type that can be converted
// using json.Marshal and json.Unmarshal. If the output is set to nil, the
// function converts to nil. If the conversion fails, it panics.
func MustAnyToAny(input any, output any) {
    err := AnyToAny(input, output)
    if err != nil {
        panic(err)
    }
}