Konstantin Shcheglov
6a9d792454
R=brianwilkerson@google.com Change-Id: I58547075d3472e6708e6b5ff1c6d89f768aba66a Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117440 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
28 lines
1.3 KiB
Dart
28 lines
1.3 KiB
Dart
// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
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// for details. All rights reserved. Use of this source code is governed by a
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// BSD-style license that can be found in the LICENSE file.
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/// Suffix indicating the nullability of a type.
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///
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/// This enum describes whether a `?` or `*` would be used at the end of the
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/// canonical representation of a type. It's subtly different the notions of
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/// "nullable", "non-nullable", "potentially nullable", and "potentially
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/// non-nullable" defined by the spec. For example, the type `Null` is
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/// nullable, even though it lacks a trailing `?`.
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enum NullabilitySuffix {
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/// An indication that the canonical representation of the type under
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/// consideration ends with `?`. Types having this nullability suffix should
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/// be interpreted as being unioned with the Null type.
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question,
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/// An indication that the canonical representation of the type under
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/// consideration ends with `*`. Types having this nullability suffix are
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/// called "legacy types"; it has not yet been determined whether they should
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/// be unioned with the Null type.
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star,
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/// An indication that the canonical representation of the type under
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/// consideration does not end with either `?` or `*`.
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none
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}
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