31 lines
1.2 KiB
Dart
31 lines
1.2 KiB
Dart
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part of symbol_table;
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/// Represents the visibility of a symbol.
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///
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/// Symbols may be [public], [protected], or [private].
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/// The significance of a symbol's visibility is semantic and specific to the interpreter/compiler;
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/// this package attaches no specific meaning to it.
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///
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/// [Visibility] instances can be compared using the `<`, `<=`, `>`, and `>=` operators.
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/// The evaluation of the aforementioned operators is logical;
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/// for example, a [private] symbol is *less visible* than a [public] symbol,
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/// so [private] < [public].
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///
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/// In a nutshell: [private] < [protected] < [public].
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class Visibility implements Comparable<Visibility> {
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static const Visibility private = const Visibility._(0);
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static const Visibility protected = const Visibility._(1);
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static const Visibility public = const Visibility._(2);
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final int _n;
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const Visibility._(this._n);
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bool operator >(Visibility other) => _n > other._n;
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bool operator >=(Visibility other) => _n >= other._n;
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bool operator <(Visibility other) => _n < other._n;
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bool operator <=(Visibility other) => _n <= other._n;
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@override
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int compareTo(Visibility other) {
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return _n.compareTo(other._n);
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}
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}
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