_oasis.diff

diff --git a/_oasis b/_oasis
index 5dcf0cc..bd22d8f 100644
--- a/_oasis
+++ b/_oasis
@@ -1,6 +1,7 @@
 OASISFormat: 0.3
 Name:        ocaml-sqlexpr
 Version:     0.7.0
+OcamlVersion: >= 4.02
 Synopsis:    Type-safe, convenient SQLite database access.
 Authors:     Mauricio Fernandez <mfp@acm.org>
 Maintainers: Mauricio Fernandez <mfp@acm.org>
@@ -62,7 +63,7 @@ Library "ppx"
 Executable "ppx_sqlexpr"
   Path:             src/ppx/
   MainIs:           ppx_sqlexpr.ml
-  BuildDepends:     unix, re.pcre, compiler-libs.common, ppx_tools.metaquot
+  BuildDepends:     unix, re.pcre, compiler-libs.common, ppx_tools.metaquot, ppx_core, ppx_driver
   CompiledObject:   best
   Install:          true

_tags.diff

+<**/*.ml{,i}>: predicate(ppx_driver)
 # OASIS_START
-# DO NOT EDIT (digest: 8c33eb34542ae662c8d9b52b2978ec0d)
+# DO NOT EDIT (digest: b3462a1e21bb04b8d345bbf3a07bf8fc)
 # Ignore VCS directories, you can use the same kind of rule outside
 # OASIS_START/STOP if you want to exclude directories that contains
 # useless stuff for the build process
@@ -16,53 +17,57 @@ true: annot, bin_annot
 "_darcs": not_hygienic
 # Library sqlexpr
 "src/sqlexpr.cmxs": use_sqlexpr
-<src/*.ml{,i,y}>: pkg_csv
-<src/*.ml{,i,y}>: pkg_estring
-<src/*.ml{,i,y}>: pkg_lwt
-<src/*.ml{,i,y}>: pkg_lwt.syntax
-<src/*.ml{,i,y}>: pkg_lwt.unix
-<src/*.ml{,i,y}>: pkg_sqlite3
-<src/*.ml{,i,y}>: pkg_threads
-<src/*.ml{,i,y}>: pkg_unix
+<src/*.ml{,i,y}>: package(csv)
+<src/*.ml{,i,y}>: package(estring)
....

ppx_sqlexpr.diff

diff --git a/src/ppx/ppx_sqlexpr.ml b/src/ppx/ppx_sqlexpr.ml
index 89ae40a..763681f 100644
--- a/src/ppx/ppx_sqlexpr.ml
+++ b/src/ppx/ppx_sqlexpr.ml
@@ -4,6 +4,9 @@ open Parsetree
 
 module AC = Ast_convenience
 
+open Ppx_core.Std
+open Ast_builder.Default
+
 let new_id =
   let n = ref 0 in
   fun () ->
@@ -127,6 +130,12 @@ let call_sqlcheck loc = function
 
 let shared_exprs = Hashtbl.create 25
 
+let shared_expr_id = function
+  | Pexp_ident {txt} ->
+      let id = Longident.last txt in
+      if Hashtbl.mem shared_exprs id then Some id else None
+  | _ -> None
+
 let register_shared_expr expr =
   let id = new_id () in
   Hashtbl.add shared_exprs id expr;
@@ -155,6 +164,16 @@ let map_expr mapper expr =
     Longident.last txt | _ -> raise Not_found end in
   [%expr let [%p AC.pvar id] = [%e get_shared_expr id] in [%e expr]]
 
+let shared_bindings = object
+  inherit [string list] Ast_traverse.fold as super
+
+  method! expression e acc =
+    let acc = super#expression e acc in
+    match shared_expr_id e.pexp_desc with
+    | Some id -> id::acc
+    | None -> acc
+end
+
 let new_mapper argv = Ast_mapper.({
   default_mapper with
   expr = (fun mapper expr ->