var text/template.errorType

4 uses

	text/template (current package)
		exec.go#L689: 	errorType        = reflect.TypeOf((*error)(nil)).Elem()
		exec.go#L1034: 	if !v.Type().Implements(errorType) && !v.Type().Implements(fmtStringerType) {
		exec.go#L1035: 		if v.CanAddr() && (reflect.PointerTo(v.Type()).Implements(errorType) || reflect.PointerTo(v.Type()).Implements(fmtStringerType)) {
		funcs.go#L118: 	case typ.NumOut() == 2 && typ.Out(1) == errorType:

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