[Proposal]: First-Class Span Types (VS 18.0, .NET 10)

[333fred]

First-Class Span Types

• Specification: https://github.com/dotnet/csharplang/blob/main/proposals/csharp-14.0/first-class-span-types.md
• Discussion: https://github.com/dotnet/csharplang/discussions/8713

Summary

We introduce first-class support for Span<T> and ReadOnlySpan<T> in the language, including new implicit conversion types and consider them in more places, allowing more natural programming with these integral types.

Design meetings

• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-02-05.md#first-class-span-types
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-05-13.md#first-class-span-types-questions
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-06-24.md#first-class-spans
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-07-15.md#first-class-spans-open-question
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-09-11.md#first-class-span-types
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-12-04.md#first-class-span-open-questions
• https://github.com/dotnet/csharplang/blob/main/meetings/2024/LDM-2024-12-09.md#first-class-span-open-questions
• https://github.com/dotnet/csharplang/blob/main/meetings/2025/LDM-2025-01-06.md#ignoring-ref-structs-in-expressions