69 lines
1.6 KiB
C#
69 lines
1.6 KiB
C#
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// Normally we wouldn't want to disable Nullable references, but in this case we want to.
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// We're assuming that if you're following Maybe conventions, you won't be hitting null ref exceptions.
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#pragma warning disable CS8601
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namespace CommonCore.Base.Structures;
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[Serializable]
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public struct Maybe<T>
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{
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private readonly T _value;
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public readonly bool HasValue;
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private Maybe(T val = default!, bool hasValue = true)
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{
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_value = val;
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HasValue = hasValue;
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}
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public T Value
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{
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get
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{
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if (!HasValue)
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throw new InvalidOperationException($"{nameof(Maybe<T>)} value is empty");
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return _value;
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}
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}
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public T OrValue(T orVal) =>
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HasValue ? Value : orVal;
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public bool Try(out T val)
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{
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val = HasValue ? Value : default;
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return HasValue;
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}
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public T OrThrow(string msg) =>
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HasValue ? Value : throw new Exception(msg);
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public Maybe<TOutput> Map<TOutput>(Func<T, TOutput> transformer) =>
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HasValue
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? Maybe<TOutput>.Create(transformer(Value))
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: Maybe<TOutput>.Empty();
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public object ToDbValue() =>
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HasValue && Value is not null
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? Value
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: DBNull.Value;
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public static Maybe<T> Create(T val, bool hasValue = true) => new(val, hasValue);
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public static Maybe<T> Create(T val, Func<T, bool> hasValue) => new(val, hasValue(val));
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public static Maybe<T> Empty() => new(default!, hasValue: false);
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public static implicit operator Maybe<T>(T val) => Create(val);
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public static explicit operator T(Maybe<T> val) => val.Value;
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public override string ToString()
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{
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return (Try(out var val)
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? val?.ToString()
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: base.ToString())!;
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}
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}
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