diff options
Diffstat (limited to 'src/mscorlib/src/System/Runtime/CompilerServices/TupleElementNamesAttribute.cs')
| -rw-r--r-- | src/mscorlib/src/System/Runtime/CompilerServices/TupleElementNamesAttribute.cs | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/src/mscorlib/src/System/Runtime/CompilerServices/TupleElementNamesAttribute.cs b/src/mscorlib/src/System/Runtime/CompilerServices/TupleElementNamesAttribute.cs new file mode 100644 index 0000000000..65b120e6b4 --- /dev/null +++ b/src/mscorlib/src/System/Runtime/CompilerServices/TupleElementNamesAttribute.cs @@ -0,0 +1,57 @@ +// Licensed to the .NET Foundation under one or more agreements. +// The .NET Foundation licenses this file to you under the MIT license. +// See the LICENSE file in the project root for more information. + +using System.Collections.Generic; + +namespace System.Runtime.CompilerServices +{ + /// <summary> + /// Indicates that the use of <see cref="System.ValueTuple"/> on a member is meant to be treated as a tuple with element names. + /// </summary> + [CLSCompliant(false)] + [AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.ReturnValue | AttributeTargets.Class | AttributeTargets.Struct | AttributeTargets.Event)] + public sealed class TupleElementNamesAttribute : Attribute + { + private readonly string[] _transformNames; + + /// <summary> + /// Initializes a new instance of the <see + /// cref="TupleElementNamesAttribute"/> class. + /// </summary> + /// <param name="transformNames"> + /// Specifies, in a pre-order depth-first traversal of a type's + /// construction, which <see cref="System.ValueType"/> occurrences are + /// meant to carry element names. + /// </param> + /// <remarks> + /// This constructor is meant to be used on types that contain an + /// instantiation of <see cref="System.ValueType"/> that contains + /// element names. For instance, if <c>C</c> is a generic type with + /// two type parameters, then a use of the constructed type <c>C{<see + /// cref="System.ValueTuple{T1, T2}"/>, <see + /// cref="System.ValueTuple{T1, T2, T3}"/></c> might be intended to + /// treat the first type argument as a tuple with element names and the + /// second as a tuple without element names. In which case, the + /// appropriate attribute specification should use a + /// <c>transformNames</c> value of <c>{ "name1", "name2", null, null, + /// null }</c>. + /// </remarks> + public TupleElementNamesAttribute(string[] transformNames) + { + if (transformNames == null) + { + throw new ArgumentNullException(nameof(transformNames)); + } + + _transformNames = transformNames; + } + + /// <summary> + /// Specifies, in a pre-order depth-first traversal of a type's + /// construction, which <see cref="System.ValueTuple"/> elements are + /// meant to carry element names. + /// </summary> + public IList<string> TransformNames => _transformNames; + } +}
\ No newline at end of file |