1 files changed, 38 insertions, 0 deletions
diff --git a/camlp4/examples/lambda_quot.ml b/camlp4/examples/lambda_quot.ml
new file mode 100644
index 000000000..654511af2
--- /dev/null
+++ b/camlp4/examples/lambda_quot.ml
@@ -0,0 +1,38 @@
+open Camlp4.PreCast;
+module CamlSyntax = Camlp4OCamlParser.Make (Camlp4OCamlRevisedParser.Make Syntax);
+
+value expr_of_string = CamlSyntax.Gram.parse_string CamlSyntax.expr_eoi;
+
+module LambdaGram = MakeGram Lexer;
+
+value term = LambdaGram.Entry.mk "term";
+value term_eoi = LambdaGram.Entry.mk "lambda term quotation";
+
+Camlp4_config.antiquotations.val := True;
+
+EXTEND LambdaGram
+  GLOBAL: term term_eoi;
+  term:
+    [ "top"
+      [ "fun"; v = var; "->"; t = term -> <:expr< `Lam $v$ $t$ >> ]
+    | "app"
+      [ t1 = SELF; t2 = SELF           -> <:expr< `App $t1$ $t2$ >> ]
+    | "simple"
+      [ `ANTIQUOT (""|"term") a        -> expr_of_string _loc a
+      | v = var                        -> <:expr< `Var $v$ >>
+      | "("; t = term; ")"             -> t ]
+    ];
+  var:
+    [[ v = LIDENT             -> <:expr< $str:v$ >>
+     | `ANTIQUOT (""|"var") a -> expr_of_string _loc a
+    ]];
+  term_eoi:
+    [[ t = term; `EOI -> t ]];
+END;
+
+value expand_lambda_quot_expr loc _loc_name_opt quotation_contents =
+  LambdaGram.parse_string term_eoi loc quotation_contents;
+
+Syntax.Quotation.add "lam" Syntax.Quotation.DynAst.expr_tag expand_lambda_quot_expr;
+
+Syntax.Quotation.default.val := "lam";