34 lines
837 B
Go
34 lines
837 B
Go
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package missinggo
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import "reflect"
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func IsZeroValue(i interface{}) bool {
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return IsEmptyValue(reflect.ValueOf(i))
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}
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// Returns whether the value represents the empty value for its type. Used for
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// example to determine if complex types satisfy the common "omitempty" tag
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// option for marshalling. Taken from
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// http://stackoverflow.com/a/23555352/149482.
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func IsEmptyValue(v reflect.Value) bool {
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switch v.Kind() {
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case reflect.Func, reflect.Map, reflect.Slice:
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return v.IsNil()
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case reflect.Array:
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z := true
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for i := 0; i < v.Len(); i++ {
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z = z && IsEmptyValue(v.Index(i))
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}
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return z
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case reflect.Struct:
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z := true
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for i := 0; i < v.NumField(); i++ {
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z = z && IsEmptyValue(v.Field(i))
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}
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return z
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}
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// Compare other types directly:
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z := reflect.Zero(v.Type())
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return v.Interface() == z.Interface()
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}
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