Restore dirname and ast label

Author: milseman

Sources/VariadicsGenerator/VariadicsGenerator.swift

@@ -157,7 +157,7 @@ struct VariadicsGenerator: ParsableCommand {
     output("  init(")
     outputForEach(0..<arity, separator: ",") { "_ x\($0): T\($0)" }
     output(") {\n")
-    output("    \(patternProtocolRequirementName) = .init(concat(\n      ")
+    output("    \(patternProtocolRequirementName) = .init(ast: concat(\n      ")
     outputForEach(
       0..<arity,
       separator: ",",