Acquired Opera AdBlock code

files/preferences.js

+const preferences = {
+        string: function(key, value) { //Gets or sets a string value
+                if(value == undefined) //Gets

[Felix Dahlke, 2012/10/08 05:57:02]

That's a bit dangerous, undefined could in fact have been defined. Better:
typeof value === "undefined"

+                        return widget.preferences.getItem(key);
+                else //Sets
+                        widget.preferences.setItem(key, value);
+        },
+        bool: function(key, value) { //Gets or sets a bool value
+                if(value == undefined) { //Gets

[Felix Dahlke, 2012/10/08 05:57:02]

See comment about the same code above.

+                        switch(widget.preferences.getItem(key)) {

[Felix Dahlke, 2012/10/08 05:57:02]

How about return key === "true" instead?

+                                case 'true':
+                                        return true;
+                                        break;
+                                default: //Returns false if the value doesn't exist
+                                        return false;
+                                        break;
+                        }
+                }
+                else { //Sets
+                        if(value)
+                                widget.preferences.setItem(key, 'true');
+                        else
+                                this.remove(key); //When set to false, remove the key to save space
+                }
+        },
+        int: function(key, value) { //Gets or sets a int value
+                if(value == undefined) { //Gets

[Felix Dahlke, 2012/10/08 05:57:02]

See comment about the same code above.

+                        value = parseInt(widget.preferences.getItem(key));
+                        if(value == NaN)

[Felix Dahlke, 2012/10/08 05:57:02]

No, this doesn't work. Use isNan().

+                                return 0; //On error return 0

[Felix Dahlke, 2012/10/08 05:57:02]

I think it's dangerous to return 0 in case of an error - is there never a
situation where we want to distinguish a not stored value from the explicit
value 0?

+                        else
+                                return value;
+                }
+                else //Sets
+                        widget.preferences.setItem(key, value);
+        },
+        float: function(key, value) { //Gets or sets a float value
+                if(value == undefined) { //Gets

[Felix Dahlke, 2012/10/08 05:57:02]

See comment about the same code above.

+                        value = parseFloat(widget.preferences.getItem(key));
+                        if(value == NaN)

[Felix Dahlke, 2012/10/08 05:57:02]

See above, use isNan()

+                                return 0; //On error return 0

[Felix Dahlke, 2012/10/08 05:57:02]

See above, not sure if this is a good idea.

+                        else
+                                return value;
+                }
+                else //Sets
+                        widget.preferences.setItem(key, value);
+        },
+        array: function(key, value) { //Gets or sets an array in the preferences
+                if(value == undefined) { //Gets

[Felix Dahlke, 2012/10/08 05:57:02]

See comment about the same code above.

+                        if(this.exist(key)) {
+                                value = widget.preferences.getItem(key);
+                                if(value.indexOf("\n") > -1)

[Felix Dahlke, 2012/10/08 05:57:02]

This whole if/else can be replaced by: return value.split("\n")

+                                        return value.split("\n");
+                                else {
+                                        return [value];
+                                }
+                        }
+                        return new Array(); //Returns an empty array when no value exists

[Felix Dahlke, 2012/10/08 05:57:02]

Shorter: return []

+                }
+                else if(value instanceof Array) { //Sets
+                        value = value.join("\n");
+                        widget.preferences.setItem(key, value);
+                }
+        },
+        invert: function(key) { //Inverts a true/false setting
+                switch(widget.preferences.getItem(key)) {

[Felix Dahlke, 2012/10/08 05:57:02]

This switch can be replaced with: widget.preferences.setItem(key, item ===
'true' ? 'false' : 'true')

+                        case 'true':
+                                widget.preferences.setItem(key, 'false');
+                                break;
+                        default:
+                                widget.preferences.setItem(key, 'true');
+                                break;
+                }
+        },
+        exist: function(key) { //Says if a preference exists

[Felix Dahlke, 2012/10/08 05:57:02]

This will return false for a numerical value set to 0, see above. Considering
that, we can just write: return !!widget.preferences.getItem(key).

This also avoids getItem being called twice.

+                if(widget.preferences.getItem(key) != null && widget.preferences.getItem(key) != '')
+                        return true;
+                return false;
+        },
+        remove: function(key) {
+                widget.preferences.removeItem(key);
+        }
+};