Add support for let ... else

Author: jonas-schievink

src/tools/rust-analyzer/lib/ungrammar/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "ungrammar"
 description = "A DSL for describing concrete syntax trees"
-version = "1.14.6"
+version = "1.14.7"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/matklad/ungrammar"
 edition = "2018"

src/tools/rust-analyzer/lib/ungrammar/rust.ungram

@@ -315,7 +315,9 @@ Stmt =
 
 LetStmt =
   Attr* 'let' Pat (':' Type)?
-  '=' initializer:Expr ';'
+  '=' initializer:Expr
+  ('else' else_branch:BlockExpr)?
+  ';'
 
 ExprStmt =
   Expr ';'?