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diff --git a/gcc/rust/ast/rust-desugar-while-let.h b/gcc/rust/ast/rust-desugar-while-let.h
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+// Copyright (C) 2025 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#ifndef RUST_DESUGAR_WHILE_LET_H
+#define RUST_DESUGAR_WHILE_LET_H
+
+#include "rust-ast-builder.h"
+#include "rust-expr.h"
+
+namespace Rust {
+namespace AST {
+
+// Desugar while-let into a set of other AST nodes. The desugar is of the
+// following form:
+//
+// ```
+// whilet let <pat> = <expr> <body>
+// ```
+//
+// becomes:
+//
+// ```
+// loop {
+//     match <expr> {
+//         <pat> => <body>,
+//         _ => break
+//     }
+// }
+// ```
+class DesugarWhileLet
+{
+public:
+  static void go (std::unique_ptr<Expr> &ptr);
+
+private:
+  DesugarWhileLet ();
+
+  struct DesugarCtx
+  {
+    DesugarCtx (location_t loc) : builder (Builder (loc)), loc (loc) {}
+
+    Builder builder;
+    location_t loc;
+
+    MatchCase make_break_arm ();
+    MatchCase make_continue_arm (std::unique_ptr<Pattern> &&pattern,
+				 std::unique_ptr<BlockExpr> &&body);
+  };
+
+  std::unique_ptr<Expr> desugar (WhileLetLoopExpr &expr);
+};
+
+} // namespace AST
+} // namespace Rust
+
+#endif // ! RUST_DESUGAR_WHILE_LET_H