using System.Runtime.CompilerServices; namespace System.Reactive.Joins { [System.Runtime.CompilerServices.NullableContext(1)] [System.Runtime.CompilerServices.Nullable(0)] public class Pattern<[System.Runtime.CompilerServices.Nullable(2)] TSource1> : Pattern { internal IObservable<TSource1> First { get; } internal Pattern(IObservable<TSource1> first) { First = first; } public Plan<TResult> Then<[System.Runtime.CompilerServices.Nullable(2)] TResult>(Func<TSource1, TResult> selector) { if (selector == null) throw new ArgumentNullException("selector"); return new System.Reactive.Joins.Plan<TSource1, TResult>(this, selector); } } }