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From Andrey Razumovsky <razumovsky.and...@gmail.com>
Subject Re: [jira] Updated: (CAY-1371) EJBQL query doesn't preserve grouping by brackets
Date Sun, 24 Jan 2010 11:09:32 GMT
4.6.6 Operators and Operator Precedence
The operators are listed below in order of *decreasing precedence*.
...
• Logical operators:
NOT
AND
OR

So e.g.
a or b and c
equals to
a or (b and c)

Actually it's the same in any language, e.g. in Java.
currently our translator has no notion of brackets around statements at all.
We could insert them everywhere (like in Andreas's patch) - but it's cleaner
insert them only when needed. So
a or b and c -- will translate to --> a or (b and c), while
a and b and c -- will translate to --> a and b and c.

And what about jjtGetParent()?

2010/1/24 Andrus Adamchik <andrus@objectstyle.org>

> As I said, I don't understand 'needBracket' logic.
>
> Per Andreas's example, the parser already does the correct grouping based
> on user specified parentheses. So all we need to do is to eagerly place "("
> and ")" around each conditional node. So Andreas's patch was doing the right
> thing (of course it also needed handling of AND and NOT).
>
> And that's what we are already doing for SelectQuery qualifiers. Although
> IIRC we have a "flattenning" algorithm to skip parentheses in uniformly
> joined 3+ term conditions.. Was that the intention of 'needBracket'?.
>
> Andrus
>
>
> On Jan 24, 2010, at 12:39 PM, Andrus Adamchik wrote:
>
>  Where does the notion of priority come from? Logically (and from the spec)
>> OR/AND/NOT all have the same priority.
>>
>> Andrus
>>
>> On Jan 24, 2010, at 12:02 PM, Andrey Razumovsky (JIRA) wrote:
>>
>>  Andrey Razumovsky updated CAY-1371:
>>> -----------------------------------
>>>
>>>  Attachment: 1371.txt
>>>
>>> Patch that fixes the issue. Not committing it just yet, because I'm not
>>> sure about patterns of expression processing. Is it correct to call
>>> jjtGetParent() ? If so, why isn't there a method with more suitable name?
>>>
>>
>>
>>
>


-- 
Andrey

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