Thank you, I missed that thread.
Since I had 12 hours (flying from Narita Japan to Detroit USA) before I saw your response, I went my way and came up with another solution using two liner plugin code which filters the paring characters and replacing them. This is attached to onWebPagePrerender event. the code looks like this.
$output = & $modx->resource->_output;
$output= preg_replace(array("/\[{/","/}\]/"),array("[[","]]"),$output);
So when showing on the page rather than executing, I would write [{snippet}] and it will be shown as [[snippet]].
<fixedpre></fixedpre> solution presented in that topic does excatly what I was doing manually and it attaches to the time of document parsing (that is, to convert the targeted characters into html codes) and it is more generalized. This is more elegant solution. why did'nt I think of that?
☆ A M B ☆