Hello monks, hoping for some insight here.

I have the following BNF and am trying to get it to work with RecDescent. I'm evaluating the WHERE condition on a simplified SQL statement.

BNF 

<cond> ::= <x> [ "OR" <cond> ]
<x>    ::= <y> [ "AND" <y> ]
<y>    ::= "(" <cond> ")" | <z> <op> <z>
<z>    ::= [tabname"."]colname | <value>
<op>   ::= "<" | ">" | "=" | "<>" | "<=" | ">="

[download]
tabname and colname are identifiers which have at most 20 characters, start with a letter, and cannot end in an underscore. colname as seen above can take the forme tabname.colname.

This is my grammar as I've converted it: 

condition : x | x /OR/i condition
x : y | y /AND/i y
y : "(" condition ")" | z OP z 
z : TABCOLNAME | COLNAME | VALUE
    
# Terminals
TABCOLNAME : /([a-z]{1}[\w]{0,18}[^_])\.([a-z]{1}[\w]{0,18}[^_\ ])/i
COLNAME : /([a-z]{1}[\w]{0,18}[^_\ ])/i
VALUE : /(\w+)/ix
OP : /(<>|<=|>=|=|<|>)/

[download]
It seems to check syntax okay put when I try to print @item after the y statement only the first part of a statement is printed. So if my string is: "ssn = 1234 and name = bob" only "ssn = 1234" gets put in @item.

Thanks for any help.

Dave

In reply to Converting BNF for use in Parse::RecDescent by Anonymous Monk

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