32 lines
1.1 KiB
C#
32 lines
1.1 KiB
C#
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using System.Diagnostics.CodeAnalysis;
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using System.Runtime.CompilerServices;
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namespace SJK.Functional;
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public sealed class None<T> : IOption<T>
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{
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public static None<T> Of() => new();
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public TResult Match<TResult>(Func<T, TResult> _, Func<TResult> onNone) =>
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onNone();
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public void Match(Action<T> onSome, Action onNone) => onNone();
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public IOption<TResult> Bind<TResult>(Func<T, IOption<TResult>> f) => new None<TResult>();
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public IOption<TResult> Map<TResult>(Func<T, TResult> f) => new None<TResult>();
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public T Or(T aDefault) => aDefault;
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public T Or(Func<T> aDefault)=>aDefault();
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public bool HasValue([NotNullWhen(true)]out T? value) => (value = default) is not null && false;
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public bool HasValue() => false;
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public override string ToString()
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{
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return nameof(None<T>);
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}
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public bool Equals(IOption<T>? other)=> other is None<T>;
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}
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