Adopt buildPartialBlock.

Transition from the old name `buildBlock(combining:into:)` to the [newly proposed](https://forums.swift.org/t/pitch-buildpartialblock-for-result-builders/55561) `buildPartialBlock(first:)` and `buildPartialBlock(accumulated:next:)`.

Requires DEVELOPMENT-SNAPSHOT-2022-03-09 or later.

Author: rxwei

README.md

@@ -8,7 +8,7 @@ See [Declarative String Processing Overview][decl-string]
 
 ## Requirements
 
-- [Swift Trunk Development Snapshot](https://www.swift.org/download/#snapshots) DEVELOPMENT-SNAPSHOT-2022-02-03 or later.
+- [Swift Trunk Development Snapshot](https://www.swift.org/download/#snapshots) DEVELOPMENT-SNAPSHOT-2022-03-09 or later.
 
 ## Integration with Swift
 

Sources/VariadicsGenerator/VariadicsGenerator.swift

@@ -234,10 +234,10 @@ struct VariadicsGenerator: ParsableCommand {
     // Emit concatenation builder.
     output("extension \(concatBuilderName) {\n")
     output("""
-        public static func buildBlock<\(genericParams)>(
-          combining next: R1, into combined: R0
+        public static func buildPartialBlock<\(genericParams)>(
+          accumulated: R0, next: R1
         ) -> \(regexTypeName)<\(matchType)> \(whereClause) {
-          .init(node: combined.regex.root.appending(next.regex.root))
+          .init(node: accumulated.regex.root.appending(next.regex.root))
         }
       }
 
@@ -248,14 +248,14 @@ struct VariadicsGenerator: ParsableCommand {
     // T + () = T
     output("""
        extension \(concatBuilderName) {
-         public static func buildBlock<W0
+         public static func buildPartialBlock<W0
        """)
     outputForEach(0..<leftArity) {
       ", C\($0)"
     }
     output("""
       , R0: \(regexComponentProtocolName), R1: \(regexComponentProtocolName)>(
-          combining next: R1, into combined: R0
+          accumulated: R0, next: R1
         ) -> \(regexTypeName)<
       """)
     if leftArity == 0 {
@@ -279,7 +279,7 @@ struct VariadicsGenerator: ParsableCommand {
     }
     output("""
         {
-          .init(node: combined.regex.root.appending(next.regex.root))
+          .init(node: accumulated.regex.root.appending(next.regex.root))
         }
       }
 
@@ -491,10 +491,10 @@ struct VariadicsGenerator: ParsableCommand {
     }()
     output("""
       extension \(altBuilderName) {
-        public static func buildBlock<\(genericParams)>(
-          combining next: R1, into combined: R0
+        public static func buildPartialBlock<\(genericParams)>(
+          accumulated: R0, next: R1
         ) -> ChoiceOf<\(matchType)> \(whereClause) {
-          .init(node: combined.regex.root.appendingAlternationCase(next.regex.root))
+          .init(node: accumulated.regex.root.appendingAlternationCase(next.regex.root))
         }
       }
 
@@ -521,7 +521,7 @@ struct VariadicsGenerator: ParsableCommand {
     let resultCaptures = (0..<arity).map { "C\($0)?" }.joined(separator: ", ")
     output("""
       extension \(altBuilderName) {
-        public static func buildBlock<\(genericParams)>(_ regex: R) -> ChoiceOf<(W, \(resultCaptures))> \(whereClause) {
+        public static func buildPartialBlock<\(genericParams)>(first regex: R) -> ChoiceOf<(W, \(resultCaptures))> \(whereClause) {
           .init(node: .alternation([regex.regex.root]))
         }
       }

Sources/_StringProcessing/RegexDSL/Builder.swift

@@ -15,9 +15,8 @@ public enum RegexComponentBuilder {
     .init(node: .empty)
   }
 
-  // TODO: Rename to `buildPartialBlock(first:)` when the feature lands.
-  public static func buildBlock<R0: RegexComponent>(_ r0: R0) -> R0 {
-    r0
+  public static func buildPartialBlock<R: RegexComponent>(first: R ) -> R {
+    first
   }
 
   public static func buildExpression<R: RegexComponent>(_ regex: R) -> R {

Sources/_StringProcessing/RegexDSL/DSL.swift

@@ -192,7 +192,9 @@ postfix operator .+
 @resultBuilder
 public struct AlternationBuilder {
   @_disfavoredOverload
-  public static func buildBlock<R: RegexComponent>(_ component: R) -> ChoiceOf<R.Match> {
+  public static func buildPartialBlock<R: RegexComponent>(
+    first component: R
+  ) -> ChoiceOf<R.Match> {
     .init(component.regex)
   }