Add support for float_of_string

Author: bobzhang

jscomp/core/js_number.ml

@@ -86,10 +86,11 @@ let is_hex_format (v : string) =
 
 let caml_float_literal_to_js_string (v : string) : string = 
   let len = String.length v in
+#if OCAML_VERSION =~ ">4.03.0"  then
   if len >= 2 && is_hex_format v then  
     to_string (float_of_string v)
   else    
-
+#end
     let rec aux buf i = 
       if i >= len then buf
       else 

jscomp/runtime/caml_format.ml

@@ -583,7 +583,9 @@ let caml_format_float fmt x =
  FIXME: arity of float_of_string is not inferred correctly
 *)
 
-let float_of_string : string -> exn ->  float  = fun%raw s exn -> {| 
+let float_of_string : string -> exn ->  float  = 
+#if OCAML_VERSION =~ ">4.3.0" then
+    fun%raw s exn -> {| 
    {
     var res = +s;
     if ((s.length > 0) && (res === res))
@@ -592,29 +594,42 @@ let float_of_string : string -> exn ->  float  = fun%raw s exn -> {|
     res = +s;
     if (((s.length > 0) && (res === res)) || /^[+-]?nan$/i.test(s)) {
         return res;
-    }
-    ;
-    if (/^ *0x[0-9a-f_]+p[+-]?[0-9_]+/i.test(s)) {
-        var pidx = s.indexOf('p');
-        pidx = (pidx == -1) ? s.indexOf('P') : pidx;
-        var exp = +s.substring(pidx + 1);
-        res = +s.substring(0, pidx);
-        return res * Math.pow(2, exp);
+    };
+    var m = /^ *([+-]?)0x([0-9a-f]+)\.?([0-9a-f]*)p([+-]?[0-9]+)/i.exec(s);
+    //            1        2             3           4
+    if(m){
+        var m3 = m[3].replace(/0+$/,'');
+        var mantissa = parseInt(m[1] + m[2] + m3, 16);
+        var exponent = (m[4]|0) - 4*m3.length;
+        res = mantissa * Math.pow(2, exponent);
+        return res;
     }
     if (/^\+?inf(inity)?$/i.test(s))
         return Infinity;
     if (/^-inf(inity)?$/i.test(s))
         return -Infinity;
     throw exn;
 }
-
 |}
-
-
-(* let float_of_string (s : string) : float = 
-  let res : float = [%raw{|+s|}] in 
-  if String.length s > 0 && res = res then res 
-  else  *)
+#else
+    fun%raw s exn -> {| 
+   {
+    var res = +s;
+    if ((s.length > 0) && (res === res))
+        return res;
+    s = s.replace(/_/g, "");
+    res = +s;
+    if (((s.length > 0) && (res === res)) || /^[+-]?nan$/i.test(s)) {
+        return res;
+    };
+    if (/^\+?inf(inity)?$/i.test(s))
+        return Infinity;
+    if (/^-inf(inity)?$/i.test(s))
+        return -Infinity;
+    throw exn;
+}
+|}
+#end
 
 let caml_float_of_string s = float_of_string s (Failure "float_of_string") 
 

jscomp/test/format_test.ml

@@ -68,13 +68,27 @@ let () =
   ;;
 #end  
 (*TODO: add scanf example *)
+
+let f loc ls  = 
+  List.iter  (fun (a,b) -> 
+  eq loc (float_of_string a) b ) ls
+
+let () = 
+    f __LOC__ [
+      "0x3.fp+1",  0x3.fp+1 ;
+      " 0x3.fp2", 0x3.fp2;
+      " 0x4.fp2", 0x4.fp2
+      ];
+    
+     
+;;
+
 #if 
   (* OCAML_VERSION =~ ">4.03.0" *) 0
 then
 
 
-let () = 
-     eq __LOC__ (float_of_string "0x3.fp+1")  0x3.fp+1;;
+
 
 let () = eq __LOC__ (Printf.sprintf "%h" 0x3.fp+1) "0x1.f8p+2"
 let () = eq __LOC__ (Printf.sprintf "%H" 0x3.fp+1) "0x1.F8P+2"