README.md

System.Text.Utf8Char

Status: Needs more work | API Ref Video

JSON Source Package

We discussed several names. Best candidates right now:

• Microsoft.Bcl.Json.Sources
• Microsoft.Text.Json.Sources

Utf8Char

• We need to think about what a down-level port would look like. I don't believe we can rev System.Memory package without breaking compat.
• ReadOnlySpan<byte> isn't convenient for UTF8 text
  • We don't really use ReadOnlySpan<byte> for text in public APIs. We have a few overloads, but they are mostly in buffer land or on brand new APIs.
• While there is some validation for individual values, this type doesn't in itself guaranteeing that any ReadOnlySpan<Utf8Char> is a valid UTF8 string (for example, it can break multi-byte sequences apart). So if UTF8 text well-formedness is critical, users still have validate. The primary benefit of having the type is to express to callers of an API what the data is supposed to represent. We can also improve debugging by making ToString() meaningful.
• This feature is useful without Utf8String. However, the feature is much less compelling without compiler support for UTF8 literals.
• IsWellFormedSequence() doesn't seem super useful. We'd want to perform validation as part of transcoding/fixup. If people don't care about the result, they can underscore the output parameter.