----------------------------------------
-- URL decodes a string
-- @param {string} str
-- @return {string}
----------------------------------------
on urldecode (str)
    res = ""
    ba = bytearray()
    len = str.length
    repeat with i = 1 to len
        c = str.char[i]
        if (c = "%") then
            -- fastest hex-to-dec conversion hack based on Lingo's rgb object
            ba.writeInt8(rgb(str.char[i+1..i+2]).blue)
            i = i + 2
        else if (c = "+") then
            ba.writeInt8(32)
        else
            ba.writeInt8(chartonum(c))
        end if
    end repeat
    ba.position = 1
    return ba.readRawString(ba.length)
end