package types
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import "reflect"
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// Go lacks a simple and safe way to see if something is a typed nil.
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// See:
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// - https://dave.cheney.net/2017/08/09/typed-nils-in-go-2
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// - https://groups.google.com/forum/#!topic/golang-nuts/wnH302gBa4I/discussion
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// - https://github.com/golang/go/issues/21538
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func isTypedNil(o interface{}) bool {
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rv := reflect.ValueOf(o)
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switch rv.Kind() {
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case reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr, reflect.Slice:
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return rv.IsNil()
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default:
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return false
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}
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}
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// Returns true if it has zero length.
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func isEmpty(o interface{}) bool {
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rv := reflect.ValueOf(o)
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switch rv.Kind() {
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case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
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return rv.Len() == 0
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default:
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return false
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}
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}
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