We add a new flag to disable the implicit import of `_StringProcessing`, similar to `-disable-implicit-concurrency-module-import`. We need this to build `_RegexParser` when `-enable-experimental-string-processing` is enabled by default, because `_StringProcessing` currently imports `_RegexParser` publicly (non-implementation-only).
Instead of returning a parser error, which results
in generic parser recovery that skips until the
next decl, return an `ErrorExpr` so we can
continue parsing.
Update the lexing code for the replacement of the
`'/.../'` and `'|...|'` delimiters with `#/.../#`
and `#|...|#` respectively, in addition to
allowing the `re'...'` delimiter.
Applies swift-experimental-string-processing#68 in regex literal type inference. Regex literals with captures will have type `Regex<Tuple{n}<Substring, {Captures...}>>`. This is a temporary thing that allows us to define generic constraints on captures. We will switch back to native tuples once we have variadic generics.
When parsing a regular expression literal, accept a serialized capture structure from the regex parser. During type checking, decode it and form Swift types.
Examples:
```swift
'/(.)(.)/' // ==> `Regex<(Substring, Substring)>`
'/(?<label>.)(.)/' // ==> `Regex<(label: Substring, Substring)`
'/((.))*((.)?)/' //==> `Regex<([Substring], [Substring], Substring, Substring?)>`
```
Also:
- Fix a bug where a regex literal parsing error is not returning an error parser result.
Note:
- This needs to land after apple/swift-experimental-string-processing#92 and after `dev/4` tag has been created.
- See apple/swift-experimental-string-processing#92 for regex parser changes and the capture structure encoding.
- The `RegexLiteralParsingFn` `CaptureStructureOut` pointer type change from `char *` to `void *` will not break builds due to implicit pointer conversion (SE-0324) and unchanged ABI.
Resolves rdar://83253511.
This reverts commit a67a0436f7, reversing
changes made to 9965df76d0.
This commit or the earlier commit this commit is based on (#40531) broke the
incremental bot.
Update the lexing implementation to defer to the
regex library, which will pass back the pointer
from to resume lexing, and update the emission to
call the new `Regex(_regexString:version:)`
overload, that will accept the regex string with
delimiters.
Because this uses the library's lexing
implementation, the delimiters are now `'/.../'`
and `'|...|'` instead of plain `'...'`.
- Checkout apple/swift-experimental-string-processing using a tag.
- Build `_MatchingEngine` as part of libswift (`ExperimentalRegex`) using sources from the package.
- Parse regex literals using the parser from `_MatchingEngine`.
- Build both `_MatchingEngine` and `_StringProcessing` as part of core libs using sources from the package.
- Use `Regex<DynamicCaptures>` as the default regex type until we finalize apple/swift-experimental-string-processing#68.
- Frontend: Implicitly import `_StringProcessing` when frontend flag `-enable-experimental-string-processing` is set.
- Type checker: Set a regex literal expression's type as `_StringProcessing.Regex<(Substring, DynamicCaptures)>`. `(Substring, DynamicCaptures)` is a temporary `Match` type that will help get us to an end-to-end working system. This will be replaced by actual type inference based a regex's pattern in a follow-up patch (soon).
- SILGen: Lower a regex literal expression to a call to `_StringProcessing.Regex.init(_regexString:)`.
- String processing runtime: Add `Regex`, `DynamicCaptures` (matching actual APIs in apple/swift-experimental-string-processing), and `Regex(_regexString:)`.
Upcoming:
- Build `_MatchingEngine` and `_StringProcessing` modules with sources from apple/swift-experimental-string-processing.
- Replace `DynamicCaptures` with inferred capture types.
These modules are part of the experimental declarative string processing feature. If accepted to the Standard Library, _StringProcessing will be available via implicit import just like _Concurrency, though _MatchingEngine will still be hidden as an implementation detail.
`_MatchingEngine` will contain the general-purpose pattern matching engine ISA, bytecode, and executor. `_StringProcessing` will contain regular expression and pattern matching APIs whose implementation depends on the matching engine..
Also consolidates frontend flag `-enable-experimental-regex` as `-enable-experimental-string-processing`.
Resolves rdar://85478647.
