Thanks, Lister. Great minds think alike :) But I was hoping for something simpler and more elegant. Anyway, I'll take a cup of coffee and finish this method finally instead of continue to write messages in this thread... :) I'll post my final version here, I promise :)

>How's this? It's pretty rough but.....
>
>CLEAR
>
>LOCAL ;
> lcStr
>
>lcStr = 'where code#parentcode.or.pcoflat="P"'
>? lcStr
>
>** You can add more symbols here as needed with a comma before and after
>lcSymbols = ",#,.or.,=,"
>
>FOR xx = 1 TO (OCCURS(",", lcSymbols))
> lcSymbol = SUBSTR(lcSymbols, AT(",", lcSymbols, xx) + 1, AT(",", lcSymbols, xx + 1) - AT(",", lcSymbols, xx) - 1)
>
> lcStr = STRTRAN(lcStr, lcSymbol, " " + lcSymbol + " ")
>ENDFOR
>
>
>? lcStr
>
>lcStr = ;
> STRTRAN(lcStr, " code ", " lnd1.Code ")
>
>lcStr = ;
> STRTRAN(lcStr, " parentcode ", " lnd1.ParentCode ")
>
>lcStr = ;
> STRTRAN(lcStr, " PCOFLAG ", " lnd1.PCOFLAG ")
>
>? lcStr
>
>
>>>If you put spaces before and after your fields names in your original lcStr, then search for the expression with the spaces before and after this should work.
>>>
>>>lcStr = ;
>>> "WHERE Code # ParentCode OR PCOFLAG = 'P'"
>>>
>>>lcStr = ;
>>> STRTRAN(lcStr, " Code ", " lnd1.Code ")
>>>
>>>lcStr = ;
>>> STRTRAN(lcStr, " ParentCode ", " lnd1.ParentCode ")
>>>
>>>lcStr = ;
>>> STRTRAN(lcStr, " PCOFLAG ", " lnd1.PCOFLAG ")
>>>
>>>
>>>Lister...
>>>
>>
>>Yes, I've realized this already :) Now the problem is to insert space before and after each symbol... Can you help me here? I'm working on it right now, if nobody has a brilliant idea how to do it without WSH.
>>>>Hi everyone,
>>>>
>>>>I have some expression, which is either filter() or for() or combination of both. I'd like to insert Alias Lnd1 before each field, which may be in this expression. Example:
>>>>

lcStr=where CODE#PARENTCODE.OR.PCOFLAG="P"

>>>>
>>>>I need to convert it to 'where lnd1.code#lnd1.parentcode OR lnd1.PCOFLAG="P"'
>>>>
>>>>I was thinking about checking this string against each field and do simple strtran, but it would not work, since I have fieldnames, which are part of other field names.
>>>>
>>>>Could you please help me?
>>>>
>>>>Thanks in advance.