aicra/datatype/builtin/int.go

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package builtin
import (
"encoding/json"
"math"
"reflect"
"git.xdrm.io/go/aicra/datatype"
)
// IntDataType is what its name tells
type IntDataType struct{}
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// Type returns the type of data
func (IntDataType) Type() reflect.Type {
return reflect.TypeOf(int(0))
}
// Build returns the validator
func (IntDataType) Build(typeName string, registry ...datatype.T) datatype.Validator {
// nothing if type not handled
if typeName != "int" {
return nil
}
return func(value interface{}) (interface{}, bool) {
switch cast := value.(type) {
case int:
return cast, true
case uint:
overflows := cast > math.MaxInt64
return int(cast), !overflows
case float64:
intVal := int(cast)
overflows := cast < float64(math.MinInt64) || cast > float64(math.MaxInt64)
return intVal, cast == float64(intVal) && !overflows
// serialized string -> try to convert to float
case string:
num := json.Number(cast)
intVal, err := num.Int64()
return int(intVal), err == nil
// serialized string -> try to convert to float
case []byte:
num := json.Number(cast)
intVal, err := num.Int64()
return int(intVal), err == nil
// unknown type
default:
return 0, false
}
}
}