(ocaml) Add support for deserialization options

parse_<typename> functions now accept an addition ?opts parameter with
de-serialization options, similar to gen_<typename>.

piqic/piqic_ocaml_ext.ml

@@ -60,8 +60,9 @@ let gen_convert mlname input_format output_format data =
 let gen_parse ocaml_mod def =
   let mlname = piqdef_mlname def in
   iod " " [
-    ios "let parse_" ^^ ios mlname; ios "x (format :Piqirun_ext.input_format) =";
-      ios "let x_pb ="; gen_convert mlname "format" "`pb" "x";
+    ios "let parse_" ^^ ios mlname;
+        ios "?opts"; ios "x (format :Piqirun_ext.input_format) =";
+      ios "let x_pb ="; gen_convert mlname "format" "`pb" "x"; ios "?opts";
       ios "in";
       ios "let buf = Piqirun.init_from_string x_pb";
       ios "in";

piqilib/piqirun_ext.mli

@@ -34,6 +34,24 @@ val init_piqi : string list -> unit
 
 val find_piqtype : string -> piqtype
 
+
+(* Construct serialization options to be passed as an optional argument to
+ * gen_<typename> and parse_<typename> functions. Available options:
+ *
+ * pretty_print
+ *
+ *      Pretty-print generated JSON and XML output (default = true)
+ *
+ * json_omit_null_fields
+ *
+ *      Omit missing optional fields from JSON output instead of representing
+ *      them as {"field_name": null} JSON fields (default = true)
+ *
+ * use_strict_parsing
+ *
+ *      Treat unknown and duplicate fields as errors when parsing JSON,
+ *      XML and Piq formats (default = false)
+ *)
 val make_options:
         ?pretty_print:bool ->
         ?json_omit_null_fields:bool ->