Remove the dbg_func and numParams options from Database.create_function, adds better docs for function creation.

Closes sql-js#139

Author: Paul Bergeron

coffee/api.coffee

@@ -427,16 +427,15 @@ class Database
             throw new Error(errmsg)
 
     ### Register a custom function with SQLite
+    @example Register a simple function
+        db.create_function("addOne", (x) -> x + 1)
+        db.exec("SELECT addOne(1)") # 2
+    
     @param name [String] the name of the function as referenced in SQL statements.
-    @param numParams [Number] the number of parameters the function expects.
     @param func [Function] the actual function to be executed.
-    @param dbg_func [Function, optional] useful for breakpointing and testing the wrapper function.
     ###
-    'create_function': (name, numParams, func, dbg_func=(->)) ->
+    'create_function': (name, func) ->
         wrapped_func = (cx, argc, argv) ->
-            # Debug function, useful for breakpointing if you need to debug this
-            dbg_func()
-
             # Parse the args from sqlite into JS objects
             args = []
             for i in [0..argc]
@@ -470,5 +469,5 @@ class Database
 
         # Generate a pointer to the wrapped, user defined function, and register with SQLite.
         func_ptr = Runtime.addFunction(wrapped_func)
-        @handleError sqlite3_create_function_v2 @db, name, numParams, SQLite.UTF8, 0, func_ptr, 0, 0, 0
+        @handleError sqlite3_create_function_v2 @db, name, func.length, SQLite.UTF8, 0, func_ptr, 0, 0, 0
         return @

coffee/worker.coffee

@@ -40,7 +40,6 @@ if typeof importScripts is 'function' # Detect webworker context
                 try
                     postMessage result, [result]
                 catch err # Some browsers fail when trying to use transferable objects
-                    console.log(err)
                     postMessage result
             when 'close'
                 db?.close()

js/sql-debug.js

@@ -275353,20 +275353,18 @@ Database = (function() {
 
 
   /* Register a custom function with SQLite
+  @example Register a simple function
+      db.create_function("addOne", (x) -> x + 1)
+      db.exec("SELECT addOne(1)") # 2
+  
   @param name [String] the name of the function as referenced in SQL statements.
-  @param numParams [Number] the number of parameters the function expects.
   @param func [Function] the actual function to be executed.
-  @param dbg_func [Function, optional] useful for breakpointing and testing the wrapper function.
    */
 
-  Database.prototype['create_function'] = function(name, numParams, func, dbg_func) {
+  Database.prototype['create_function'] = function(name, func) {
     var func_ptr, wrapped_func;
-    if (dbg_func == null) {
-      dbg_func = (function() {});
-    }
     wrapped_func = function(cx, argc, argv) {
       var arg, args, data_func, i, k, ref, result, value_ptr, value_type;
-      dbg_func();
       args = [];
       for (i = k = 0, ref = argc; 0 <= ref ? k <= ref : k >= ref; i = 0 <= ref ? ++k : --k) {
         value_ptr = getValue(argv + (4 * i), 'i32');
@@ -275412,7 +275410,7 @@ Database = (function() {
       }
     };
     func_ptr = Runtime.addFunction(wrapped_func);
-    this.handleError(sqlite3_create_function_v2(this.db, name, numParams, SQLite.UTF8, 0, func_ptr, 0, 0, 0));
+    this.handleError(sqlite3_create_function_v2(this.db, name, func.length, SQLite.UTF8, 0, func_ptr, 0, 0, 0));
     return this;
   };