1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
package arg
import (
"encoding"
"reflect"
scalar "github.com/alexflint/go-scalar"
)
var textUnmarshalerType = reflect.TypeOf([]encoding.TextUnmarshaler{}).Elem()
// canParse returns true if the type can be parsed from a string
func canParse(t reflect.Type) (parseable, boolean, multiple bool) {
parseable = scalar.CanParse(t)
boolean = isBoolean(t)
if parseable {
return
}
// Look inside pointer types
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
// Look inside slice types
if t.Kind() == reflect.Slice {
multiple = true
t = t.Elem()
}
parseable = scalar.CanParse(t)
boolean = isBoolean(t)
if parseable {
return
}
// Look inside pointer types (again, in case of []*Type)
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
parseable = scalar.CanParse(t)
boolean = isBoolean(t)
if parseable {
return
}
return false, false, false
}
// isBoolean returns true if the type can be parsed from a single string
func isBoolean(t reflect.Type) bool {
switch {
case t.Implements(textUnmarshalerType):
return false
case t.Kind() == reflect.Bool:
return true
case t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Bool:
return true
default:
return false
}
}
|
