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Regarding rule precedence and Optional Category [message #1722314]

Thu, 04 February 2016 07:16

pranay roy is currently offline

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I am trying to create a grammar for a scenario where

1. Categories are optional
2. Category are conditional (Some can exist only if a particular category already exists in the statement)
3. Categories can occur at Multiple places

"plot profit by Month for Jim"

Here,
-Can Occur at multiple places :
"by Month" can occur anywhere after "plot profit" . (not just after "plot profit")
So,plot profit for Jim by Month is also valid

-Conditional
"by Month" should occur only if "plot profit" exists

--Optional
It may not occur at all.

My Grammar looks like this :

(key=QTypekeyWord)? measure=MeasureList (by='by'groupBy=GroupBy)?

QTypekeyWord:
qKeyword='plot'
;
MeasureList : names+=Measure ("," names+=Measure)*;
Measure:ID+;

Dimension:
dimension=ID
;

GroupBy:
group+= Dimension ('and' group+=Dimension)*

But it does not imply all three points. Please let me know if there is a succinct way to represent the grammar.

Should I use " | " to represent all the possibilities of statements or there are other ways.

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Re: Regarding rule precedence and Optional Category [message #1722317 is a reply to message #1722314]

Thu, 04 February 2016 07:25

Christian Dietrich is currently offline

Christian Dietrich

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Hi,

can you give a sample model as well? i dont see categeories in your grammar?

some general hint:

- you do not have to encode everything in your grammar. it often helps to move rules to a semantic validation (check method in the validator)
- you can use unordered groups if you want to have grammar stuff in any order

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Re: Regarding rule precedence and Optional Category [message #1722321 is a reply to message #1722317]

Thu, 04 February 2016 07:30

pranay roy is currently offline

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Messages: 196
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Thanks for the reply.

I wish to have content assist work at any place in a statement like above instead of validation.

Its the dummy one I am using .

Model:
message=Query;

please correct me if I am missing something. Or provide some resource to create a grammar with such requirements. Any examples other than what is mentioned in the doc?

[Updated on: Thu, 04 February 2016 07:30]

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Re: Regarding rule precedence and Optional Category [message #1722323 is a reply to message #1722321]

Thu, 04 February 2016 07:40

Christian Dietrich is currently offline

Christian Dietrich

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you can implement the filtering in the content assist and or scoping as well, but this depends on your concepts.
in the grammar you posted there are IDs only so i do not get any clue how to give further advice.
can you give a complete grammar and model i can simply copy and paste?

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Re: Regarding rule precedence and Optional Category [message #1722325 is a reply to message #1722323]

Thu, 04 February 2016 07:49

pranay roy is currently offline

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This is the sample grammar that I am using. I am using this to achieve all three points I stated above. For simplicity I just added ID. You can change the value to any random string as I mentioned in my example.

Model:
greetings=Query;

Query:
(key=QTypekeyWord)?measure=MeasureList (by='by'groupBy=GroupBy)?

QTypekeyWord:
qKeyword='plot'
;

MeasureList : names+=Measure ("," names+=Measure)*;
Measure:ID+;

GroupBy:
group+= Dimension ('and' group+=Dimension)* ;

Dimension:
dimension=ID
;

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Re: Regarding rule precedence and Optional Category [message #1722327 is a reply to message #1722325]

Thu, 04 February 2016 07:52

Christian Dietrich is currently offline

Christian Dietrich

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Hi,

yes but this gramamr say: the by comes at the end.

so isnt your semantics

Query:
(key=QTypekeyWord)? parts+=QueryPart+;

QueryPart:
measure=MeasureList (by='by'groupBy=GroupBy)? ;

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Re: Regarding rule precedence and Optional Category [message #1722329 is a reply to message #1722327]

Thu, 04 February 2016 07:54

pranay roy is currently offline

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Yeah. It is not complete . I am not sure how to have it conditioned and unordered.

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Re: Regarding rule precedence and Optional Category [message #1722330 is a reply to message #1722329]

Thu, 04 February 2016 07:57

Christian Dietrich is currently offline

Christian Dietrich

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you cannot have conditioned if the decision is static. so what is the condition in your example

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Re: Regarding rule precedence and Optional Category [message #1722332 is a reply to message #1722330]

Thu, 04 February 2016 08:00

Christian Dietrich is currently offline

Christian Dietrich

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and where is the unordered thing? a group always comes after the measures.

but maybe your grammar is just a mixed list of dimensions and bys?

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Re: Regarding rule precedence and Optional Category [message #1722339 is a reply to message #1722332]

Thu, 04 February 2016 08:14

pranay roy is currently offline

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yeah I know there is no condition and unordering. I want to convert this grammar to achieve the three points I mentioned.

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Re: Regarding rule precedence and Optional Category [message #1722342 is a reply to message #1722339]

Thu, 04 February 2016 08:27

Christian Dietrich is currently offline

Christian Dietrich

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Messages: 14075
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yes
1. Categories are optional and 3. Categories can occur at Multiple places can be done if you reorganize the grammar

but 2. Category are conditional (Some can exist only if a particular category already exists in the statement) cannot be hardcoded to the grammar.
=> you have to adapt scope provider and/or contentassist

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Re: Regarding rule precedence and Optional Category [message #1722347 is a reply to message #1722342]

Thu, 04 February 2016 09:05

pranay roy is currently offline

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Ok Thank you.Could you please direct me to 3 .any examples.?

[Updated on: Thu, 04 February 2016 09:08]

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Re: Regarding rule precedence and Optional Category [message #1722348 is a reply to message #1722347]

Thu, 04 February 2016 09:08

Christian Dietrich is currently offline

Christian Dietrich

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Model: (list+=StuffOfKindA|list+=StuffOfKindB)+

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Re: Regarding rule precedence and Optional Category [message #1722349 is a reply to message #1722348]

Thu, 04 February 2016 09:11

Christian Dietrich is currently offline

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or

Model:
stuff+=Stuff+;

Stuff: ... (optionalForStuff=OptionalThing)?

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Re: Regarding rule precedence and Optional Category [message #1722350 is a reply to message #1722349]

Thu, 04 February 2016 09:17

Christian Dietrich is currently offline

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or if the optional and the required stuff should have any order

Model: parts+=Part+;

Part: (required=Required) & (optional=Optional)?

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Re: Regarding rule precedence and Optional Category [message #1722358 is a reply to message #1722350]

Thu, 04 February 2016 09:38

pranay roy is currently offline

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So in the following :

(key=QTypekeyWord)? measure=MeasureList (by='by'groupBy=GroupBy)?

In this pattern , QTypeWord and GroupBy are optionals.

while measure=MeasureList is mandatory .

what difference is it to

(key=QTypekeyWord)? (measure=MeasureList)& (by='by'groupBy=GroupBy)?

How do I change it such that even empty state is accepted by the grammar. Right now I am getting a" ()+ did not match any thing at input. Is this because of grammar" in the UI editor. Haven't been able to figure it out .

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Re: Regarding rule precedence and Optional Category [message #1722362 is a reply to message #1722358]

Thu, 04 February 2016 10:08

Christian Dietrich is currently offline

Christian Dietrich

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Messages: 14075
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Hi,

i still dont get the requirements and semantics of your sample

Model:
greetings=Query;

Query:
(key=QTypekeyWord)? measures+=MeasureList+
;

QTypekeyWord:
qKeyword='plot'
;

MeasureList : names+=Measure ("," names+=Measure)* (by?='by'groupBy=GroupBy)?;
Measure:=> ID+;


GroupBy:
group+= Dimension ('and' group+=Dimension)* ;

Dimension:
dimension=ID
;

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Re: Regarding rule precedence and Optional Category [message #1722366 is a reply to message #1722362]

Thu, 04 February 2016 10:28

pranay roy is currently offline

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Messages: 196
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Model:
greetings=Query;

Query:
(key=QTypekeyWord)? measures+=MeasureList+ (by='by'groupBy=GroupBy)? (condition=Condtition)? 
;

QTypekeyWord:
qKeyword='plot'
;

MeasureList : names+=Measure ("," names+=Measure)* (by?='by'groupBy=GroupBy)?;
Measure:=> ID+;


GroupBy:
group+= Dimension ('and' group+=Dimension)* ;

Dimension:
dimension=ID
;

DimensionValue:
	value=ID
;

Condtition:
	con='for' dimVal=DimensionValue 
;

I have added condition category to express my point better.
In this example I am trying to match "plot profit by country for tim".

However, in the grammar when I do "plot profit for tim" . the "by" clause is not expected after tim. because my grammar has a place for condition (which is last).

ideally ,
I want to change this grammar such that when I provide "plot profit for tim" it should be able to accept by after tim.

as "by" and "condition" can be interchangeable and should not hold a specific place in a statement

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Re: Regarding rule precedence and Optional Category [message #1722367 is a reply to message #1722366]

Thu, 04 February 2016 10:30

Christian Dietrich is currently offline

Christian Dietrich

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this is what unordered groups do

((by='by'groupBy=GroupBy)? &(condition=Condtition)? )

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Re: Regarding rule precedence and Optional Category [message #1722458 is a reply to message #1722367]

Fri, 05 February 2016 03:00

pranay roy is currently offline

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Messages: 196
Registered: January 2016

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Thank you for this. It worked Smile

Smile

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