listtypes.go

package myflags

import (
	"fmt"
	"reflect"
	"strconv"
)

// these are needed to support slice/array of the types
func init() {
	Register[string](new(strType))
	Register[float32](&floatType{len: 32})
	Register[float64](&floatType{len: 64})
	Register[bool](new(boolType))
}

type strType string

func (s *strType) ToStr(in any, tag reflect.StructTag) string {
	if reflect.ValueOf(in).Kind() == reflect.Pointer {
		return *(in.(*string))
	}
	return in.(string)

}

func (s *strType) FromStr(input string, tag reflect.StructTag) (any, error) {
	return input, nil
}

type boolType bool

func (b *boolType) ToStr(in any, tag reflect.StructTag) string {
	if reflect.ValueOf(in).Kind() == reflect.Pointer {
		return fmt.Sprint(*(in.(*bool)))
	}
	return fmt.Sprint(in)
}
func (b *boolType) FromStr(input string, tag reflect.StructTag) (any, error) {
	return strconv.ParseBool(input)
}

type floatType struct {
	len int
}

func (f *floatType) ToStr(in any, tag reflect.StructTag) string {
	//if in is a pointer, convert it to the value
	val := reflect.ValueOf(in)
	if val.Kind() == reflect.Pointer {
		val = val.Elem()
	}
	return fmt.Sprint(val.Interface())
}
func (f *floatType) FromStr(s string, tag reflect.StructTag) (any, error) {
	f64, err := strconv.ParseFloat(s, f.len)
	if err != nil {
		return 0, nil
	}
	switch f.len {
	case 32:
		return float32(f64), nil

	}
	return f64, nil
}