--- /dev/null
+(* $Id$ *)
+
+open Printf
+
+(* HTML simulator (first in its kind) *)
+
+type html_tag =
+ [ `T of string
+ | `L of html_tag list
+ | `BR
+ | `DIV of int * string option * html_tag
+ ]
+
+type html_msg = [ `Error of html_tag | `Msg of html_tag ]
+
+type logger_fun = ?append_NL:bool -> html_msg -> unit
+
+let rec string_of_html_tag =
+ let rec aux indent =
+ let indent_str = String.make indent ' ' in
+ function
+ | `T s -> s
+ | `L msgs ->
+ String.concat ("\n" ^ indent_str) (List.map (aux indent) msgs)
+ | `BR -> "\n" ^ indent_str
+ | `DIV (local_indent, _, tag) ->
+ "\n" ^ indent_str ^ aux (indent + local_indent) tag
+ in
+ aux 0
+
+let string_of_html_msg = function
+ | `Error tag -> "Error: " ^ string_of_html_tag tag
+ | `Msg tag -> string_of_html_tag tag
+
+let rec html_of_html_tag = function
+ | `T s -> s
+ | `L msgs ->
+ sprintf "<ul>\n%s\n</ul>"
+ (String.concat "\n"
+ (List.map
+ (fun msg -> sprintf "<li>%s</li>" (html_of_html_tag msg))
+ msgs))
+ | `BR -> "<br />\n"
+ | `DIV (indent, color, tag) ->
+ sprintf "<div style=\"%smargin-left:%fcm\">\n%s\n</div>"
+ (match color with None -> "" | Some color -> "color: " ^ color ^ "; ")
+ (float_of_int indent *. 0.5)
+ (html_of_html_tag tag)
+
+let html_of_html_msg =
+ function
+ | `Error tag -> "<b>Error: " ^ html_of_html_tag tag ^ "</b>"
+ | `Msg tag -> html_of_html_tag tag
+
+let log_callbacks = ref []
+
+let register_log_callback logger_fun =
+ log_callbacks := !log_callbacks @ [ logger_fun ]
+
+let log ?append_NL html_msg =
+ List.iter (fun logger_fun -> logger_fun ?append_NL html_msg) !log_callbacks
+