private void FsSource_TextChanged(object sender, TextChangedEventArgs e)
{
e.ChangedRange.ClearStyle();
e.ChangedRange.SetStyle(_style, @"^(?<range>[\w\s]+\b(function|contract|return|string|uint|bytes|bytes32)\s+[\w<>,\s]+)|^\s*(function|contract|return|string|uint|bytes|bytes32)[^\n]+(\n?\s*{|;)?");
}