Ubiquity.NET.Extensions 20.1.8-delta

About

Ubiquity.NET.Extensions contains general extensions for .NET. This is a bit of a "grab bag" of functionality used by but not actually part of multiple other Ubiquity.NET projects.

Key support

• Computing a hash code for a ReadOnlySpan of bytes using System.IO.System.IO.Hashing.XxHash3
• DisposableAction for building actions that must occur on Dispose
  • This is useful for implementing the RAII pattern in .NET.
• MustUseReturnValueAttribute that is compatible with the MustUseRetVal package.
• StringNormalizer extensions to support converting line endings of strings for interoperability across OS platforms and compatibility with "on disk" representations.
• A custom ValidatedNotNullAttribute to allow compiler to assume a parameter value is validated as not null.
• Fluent style parameter value validation extensions.
  • These are useful when passing parameters to a function that produces a result that is fed to the base constructor. These are also useful in body expressions to validate input parameters.
• DictionaryBuilder to enable dictionary initializer style initialization of ImmutableDictionary<TKey, TValue> with significantly reduced overhead.
  • This leverages an ImmutableDictionary<TKey, TValue>.Builder under the hood to build the dictionary. When the ToImmutable() method is called the builder is converted to the immutable state without any overhead of a copy or re-construction of hash tables etc...
• KvpArrayBuilder to enable array initializer style initialization of ImmutableArray<KeyValuePair<TKey, TValue>> with significantly reduced overhead.
  • This leverages an ImmutableArray<T>.Builder under the hood to build the array directly. When the ToImmutable() method is called the builder is converted to the immutable state without any overhead of a copy.
  • Since this is an array and not a dictionary there is no overhead for allocating, initializing or copying any hash mapping for the keys.

Fluent Validation

The library includes extensions that support fluent validation to allow use in property accessors and constructors that forward values to a base or another constructor. This is normally used when the value itself isn't passed on but some transformed value is.

• ThrowIfNull()
• ThrowIfOutOfRange()
• ThrowIfNotDefined()

PolyFill

While it isn't impossible to make polyfill this to work on .NET standard 2.0 it is a HUGE amount of effort to do so and there's no compelling reason to do so. Roslyn extensions/VSIX extensions are the most likely candidates left. VS extensions are shifting to external processes for extensions for this reason, leaving Roslyn generators. The bottom line is that too much of MODERN .NET and C# is incompatible with .NET Standard 2.0 that a distinct PolyFill library can only cover some of it. (Even the PolySharp generator covers only some of the missing functionality)