[r2004-05-11 22:44:26 by afrisch] Fixed an extremely embarassing bug which...

[r2004-05-11 22:44:26 by afrisch] Fixed an extremely embarassing bug which made ("" @ "a") segfaults...

Original author: afrisch
Date: 2004-05-11 22:44:27+00:00

depend

@@ -214,26 +214,48 @@ types/builtin.cmx: types/atoms.cmx types/builtin_defs.cmx types/chars.cmx \
     runtime/value.cmx types/builtin.cmi 
 driver/librarian.cmo: types/builtin.cmi compile/compile.cmi \
     misc/encodings.cmi runtime/eval.cmi types/ident.cmo compile/lambda.cmo \
-    parser/location.cmi parser/parser.cmi types/sequence.cmi \
-    misc/serialize.cmi typing/typer.cmi types/types.cmi runtime/value.cmi \
-    driver/librarian.cmi 
+    parser/location.cmi parser/parser.cmi misc/serialize.cmi typing/typer.cmi \
+    types/types.cmi runtime/value.cmi driver/librarian.cmi 
 driver/librarian.cmx: types/builtin.cmx compile/compile.cmx \
     misc/encodings.cmx runtime/eval.cmx types/ident.cmx compile/lambda.cmx \
-    parser/location.cmx parser/parser.cmx types/sequence.cmx \
-    misc/serialize.cmx typing/typer.cmx types/types.cmx runtime/value.cmx \
-    driver/librarian.cmi 
+    parser/location.cmx parser/parser.cmx misc/serialize.cmx typing/typer.cmx \
+    types/types.cmx runtime/value.cmx driver/librarian.cmi 
+cdo2cmo/ml_types.cmo: types/types.cmi 
+cdo2cmo/ml_types.cmx: types/types.cmx 
+cdo2cmo/ml_cduce.cmo: types/atoms.cmi types/builtin_defs.cmi types/chars.cmi \
+    compile/compile.cmi misc/encodings.cmi types/ident.cmo \
+    types/intervals.cmi compile/lambda.cmo driver/librarian.cmi \
+    cdo2cmo/ml_types.cmo misc/ns.cmi types/sequence.cmi typing/typer.cmi \
+    types/types.cmi 
+cdo2cmo/ml_cduce.cmx: types/atoms.cmx types/builtin_defs.cmx types/chars.cmx \
+    compile/compile.cmx misc/encodings.cmx types/ident.cmx \
+    types/intervals.cmx compile/lambda.cmx driver/librarian.cmx \
+    cdo2cmo/ml_types.cmx misc/ns.cmx types/sequence.cmx typing/typer.cmx \
+    types/types.cmx 
+cdo2cmo/ml_ocaml.cmo: driver/librarian.cmi cdo2cmo/ml_types.cmo 
+cdo2cmo/ml_ocaml.cmx: driver/librarian.cmx cdo2cmo/ml_types.cmx 
+cdo2cmo/ml_checker.cmo: cdo2cmo/ml_cduce.cmo cdo2cmo/ml_ocaml.cmo \
+    cdo2cmo/ml_types.cmo 
+cdo2cmo/ml_checker.cmx: cdo2cmo/ml_cduce.cmx cdo2cmo/ml_ocaml.cmx \
+    cdo2cmo/ml_types.cmx 
+cdo2cmo/ml_generator.cmo: cdo2cmo/ml_cduce.cmo cdo2cmo/ml_ocaml.cmo \
+    cdo2cmo/ml_types.cmo 
+cdo2cmo/ml_generator.cmx: cdo2cmo/ml_cduce.cmx cdo2cmo/ml_ocaml.cmx \
+    cdo2cmo/ml_types.cmx 
 driver/cduce.cmo: parser/ast.cmo types/builtin.cmi compile/compile.cmi \
     misc/encodings.cmi runtime/eval.cmi runtime/explain.cmi types/ident.cmo \
-    driver/librarian.cmi parser/location.cmi misc/ns.cmi parser/parser.cmi \
-    types/patterns.cmi types/sample.cmi schema/schema_common.cmi \
-    misc/state.cmi typing/typer.cmi types/types.cmi parser/ulexer.cmi \
-    runtime/value.cmi driver/cduce.cmi 
+    driver/librarian.cmi parser/location.cmi cdo2cmo/ml_cduce.cmo \
+    cdo2cmo/ml_checker.cmo cdo2cmo/ml_generator.cmo cdo2cmo/ml_ocaml.cmo \
+    misc/ns.cmi parser/parser.cmi types/patterns.cmi types/sample.cmi \
+    schema/schema_common.cmi misc/state.cmi typing/typer.cmi types/types.cmi \
+    parser/ulexer.cmi runtime/value.cmi driver/cduce.cmi 
 driver/cduce.cmx: parser/ast.cmx types/builtin.cmx compile/compile.cmx \
     misc/encodings.cmx runtime/eval.cmx runtime/explain.cmx types/ident.cmx \
-    driver/librarian.cmx parser/location.cmx misc/ns.cmx parser/parser.cmx \
-    types/patterns.cmx types/sample.cmx schema/schema_common.cmx \
-    misc/state.cmx typing/typer.cmx types/types.cmx parser/ulexer.cmx \
-    runtime/value.cmx driver/cduce.cmi 
+    driver/librarian.cmx parser/location.cmx cdo2cmo/ml_cduce.cmx \
+    cdo2cmo/ml_checker.cmx cdo2cmo/ml_generator.cmx cdo2cmo/ml_ocaml.cmx \
+    misc/ns.cmx parser/parser.cmx types/patterns.cmx types/sample.cmx \
+    schema/schema_common.cmx misc/state.cmx typing/typer.cmx types/types.cmx \
+    parser/ulexer.cmx runtime/value.cmx driver/cduce.cmi 
 query/query.cmo: parser/ast.cmo types/atoms.cmi types/builtin_defs.cmi \
     types/chars.cmi types/ident.cmo types/intervals.cmi parser/location.cmi \
     parser/parser.cmi types/types.cmi query/query.cmi 
@@ -246,12 +268,12 @@ query/query_parse.cmo: parser/ast.cmo types/atoms.cmi types/ident.cmo \
 query/query_parse.cmx: parser/ast.cmx types/atoms.cmx types/ident.cmx \
     parser/location.cmx parser/parser.cmx query/query.cmx types/sequence.cmx \
     types/types.cmx 
-driver/run.cmo: driver/cduce.cmi types/ident.cmo driver/librarian.cmi \
-    runtime/load_xml.cmi parser/location.cmi types/sequence.cmi \
+driver/run.cmo: types/builtin.cmi driver/cduce.cmi types/ident.cmo \
+    driver/librarian.cmi runtime/load_xml.cmi parser/location.cmi \
     misc/state.cmi misc/stats.cmi parser/ulexer.cmi parser/url.cmi \
     runtime/value.cmi 
-driver/run.cmx: driver/cduce.cmx types/ident.cmx driver/librarian.cmx \
-    runtime/load_xml.cmx parser/location.cmx types/sequence.cmx \
+driver/run.cmx: types/builtin.cmx driver/cduce.cmx types/ident.cmx \
+    driver/librarian.cmx runtime/load_xml.cmx parser/location.cmx \
     misc/state.cmx misc/stats.cmx parser/ulexer.cmx parser/url.cmx \
     runtime/value.cmx 
 driver/webiface.cmo: driver/cduce.cmi driver/examples.cmo parser/location.cmi \
@@ -307,9 +329,8 @@ compile/compile.cmi: parser/ast.cmo types/ident.cmo compile/lambda.cmo \
     runtime/value.cmi 
 compile/operators.cmi: misc/custom.cmo parser/location.cmi misc/serialize.cmi \
     typing/typer.cmi types/types.cmi runtime/value.cmi 
-types/builtin.cmi: typing/typer.cmi 
-driver/librarian.cmi: types/types.cmi runtime/value.cmi 
-driver/cduce.cmi: types/ident.cmo types/types.cmi runtime/value.cmi 
+types/builtin.cmi: typing/typer.cmi runtime/value.cmi 
+driver/librarian.cmi: types/types.cmi 
 query/query.cmi: parser/ast.cmo 
 schema/schema_types.cmi: misc/encodings.cmi types/intervals.cmi misc/ns.cmi \
     runtime/value.cmi 

runtime/eval.ml

@@ -100,7 +100,7 @@ let rec eval env = function
       let v3 = eval env e3 in
       Value.Xml (v1,v2,v3)
   | Record r -> Value.Record (LabelMap.map (eval env) r)
-  | String (i,j,s,q) -> Value.String_utf8 (i,j,s,eval env q)
+  | String (i,j,s,q) -> Value.substring_utf8 i j s (eval env q)
   | Match (e,brs) -> eval_branches env brs (eval env e)
 
   | Map (arg,brs) -> eval_map env brs (eval env arg)

runtime/value.ml

@@ -18,12 +18,25 @@ type t =
 
   | Delayed of t ref
 
+(* 
+  The only representation of the empty sequence is nil.
+  In particular, in String_latin1 and String_utf8, the string cannot be empty.
+*)
+
+let dump_forward = ref (fun _ _ -> assert false)
 
 exception CDuceExn of t
 
 let nil = Atom Sequence.nil_atom
-let string_latin1 s = String_latin1 (0,String.length s, s, nil)
-let string_utf8 s = String_utf8 (Utf8.start_index s,Utf8.end_index s, s, nil)
+let string_latin1 s = 
+  if String.length s = 0 then nil
+  else String_latin1 (0,String.length s, s, nil)
+let string_utf8 s = 
+  if String.length (Utf8.get_str s) = 0 then nil
+  else String_utf8 (Utf8.start_index s,Utf8.end_index s, s, nil)
+let substring_utf8 i j s q =
+  if Utf8.equal_index i j then q 
+  else String_utf8 (i,j,s,q)
 let vtrue = Atom (Atoms.V.mk_ascii "true")
 let vfalse = Atom (Atoms.V.mk_ascii "false")
 let vbool x = if x then vtrue else vfalse
@@ -513,3 +526,4 @@ let rec flatten = function
 let failwith' s = raise (CDuceExn (string_latin1 s))
 let raise' v = raise (CDuceExn v)
 
+let () = dump_forward := dump_xml

runtime/value.mli

@@ -40,6 +40,7 @@ val const : Types.const -> t  (* extract the const value from a const type *)
 val inv_const : t -> Types.const  (* build a const type from a const value *)
 val string_latin1 : string -> t
 val string_utf8 : U.t -> t
+val substring_utf8: U.uindex -> U.uindex -> U.t -> t -> t
 val nil : t
 val vtrue : t
 val vfalse : t

web/hacking.xml

 <?xml version="1.0" encoding="ISO-8859-1" standalone="yes"?>
-<page name="hacking">
+<page name="hacking" new="">
 
 <title>Hacking CDuce</title>
 

web/index.xml

@@ -21,6 +21,7 @@
 <include file="documentation.xml"/>
 <include file="examples.xml"/>
 <include file="hacking.xml"/>
+<include file="tips.xml"/>
 <include file="mailing.xml"/>
 <include file="team.xml"/>
 <include file="sitemap.xml"/>

web/tips.xml

+<?xml version="1.0" encoding="ISO-8859-1" standalone="yes"?>
+<page name="tips">
+
+<title>Tips and Tricks with CDuce</title>
+
+
+<box title="Poor-man ML-like polymorphism" link="pmpoly">
+<p>
+CDuce does not currently support ML-like parametric polymorphism.
+For instance, a <code>fold_left</code> function can be defined
+for arbitrary fixed types, but not in a polymorphic way.
+Here is one possible definition:
+</p>
+<sample>
+let fold_left (f : ((A,B) -> A), x : A, l : [B*]) : A =
+ let accu = ref A x in
+ (transform l with y -> accu := f (!accu,y));
+ !accu
+</sample>
+<p>
+Of course, it is possible to set <code>A=B=Any</code>, but then
+one looses all the type information.
+</p>
+<p>
+A technique which was suggested by Serge Leblanc on the CDuce users
+mailing list is to rely on the <code>include</code> feature.
+Here is an example, which assumes that the above piece of code is in a
+file <code>fold_left.cd</code>:
+</p>
+<sample>
+type A = Int
+type B = Int
+include "fold_left.cd";;
+let fold_int_int = fold_left
+
+type A = Latin1
+type B = Any
+include "fold_left.cd";;
+let fold_string_any = fold_left
+
+let s1 = fold_int_int 
+ ((fun (x : Int, y : Int) : Int = x + y), 0, [ 1 2 3 ])
+
+let s2 = fold_string_any
+ ((fun (x : Latin1, y : Any) : Latin1 = x @ (string_of y)), "",[ 1 `x 'a' ])
+</sample>
+<p>
+Of course, this is nothing but textual substitution, and this could
+also be handled through a general-purpose preprocessor such as
+cpp or m4.
+</p>
+</box>
+
+</page>