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PetitParser handling preprocessor directives?

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Stephan Eggermont-3

PetitParser handling preprocessor directives?

Hi

What is the best way to handle pre-processor directives with PetitParser without polluting
the parsing too much? Any suggestions?

unit forms;
interface
{$IFDEF WINDOWS}
uses bla;
{$ENDIF}
{$IFDEF LINUX}
uses bla2;
{$ENDIF}

Diego & Stephan

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Guillermo Polito

Re: PetitParser handling preprocessor directives?

Maybe you can use a -completely separate- pre-parser? :)

It takes the input with the pre processor directives, and answers a new processed string which the original parser will handle?.

Guille

On Thu, Sep 13, 2012 at 3:22 PM, Stephan Eggermont <[hidden email]> wrote:

Hi

What is the best way to handle pre-processor directives with PetitParser without polluting
the parsing too much? Any suggestions?

unit forms;
interface
{$IFDEF WINDOWS}
uses bla;
{$ENDIF}
{$IFDEF LINUX}
uses bla2;
{$ENDIF}

Diego & Stephan

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Guillaume Larcheveque

Re: PetitParser handling preprocessor directives?

You can use PetitPreprocessor:

Gofer new
    squeaksource3: 'PetitPreprocessor';
    package: 'PetitPreprocessor';
    load

Now it's just transform a matching regex to a substitution String (MyParser preProcess: ('toPreprocess' asRegex) into: 'preProcessed' ) but I plan to improve it by providing a PParser to detect a matching and apply its transformation block (myParser preProcessor: (matchingParser ==> [:m | ..... ])).

2012/9/13 Guillermo Polito <[hidden email]>

Maybe you can use a -completely separate- pre-parser? :)

It takes the input with the pre processor directives, and answers a new processed string which the original parser will handle?.

Guille

On Thu, Sep 13, 2012 at 3:22 PM, Stephan Eggermont <[hidden email]> wrote:

Hi

What is the best way to handle pre-processor directives with PetitParser without polluting
the parsing too much? Any suggestions?

unit forms;
interface
{$IFDEF WINDOWS}
uses bla;
{$ENDIF}
{$IFDEF LINUX}
uses bla2;
{$ENDIF}

Diego & Stephan

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--
Guillaume Larcheveque

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Stephan Eggermont-3

Re: PetitParser handling preprocessor directives?

In reply to this post by Stephan Eggermont-3

Guillaume wrote:

>You can use PetitPreprocessor:
>Gofer new
> squeaksource3: 'PetitPreprocessor';
> package: 'PetitPreprocessor';
> load
>
>Now it's just transform a matching regex to a substitution String (MyParser
>preProcess: ('toPreprocess' asRegex) into: 'preProcessed' ) but I plan to
>improve it by providing a PParser to detect a matching and apply its
>transformation block (myParser preProcessor: (matchingParser ==> [:m |
>..... ])).

Thank you. Will try that first

Stephan

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Stephan Eggermont-3

Re: PetitParser handling preprocessor directives?

In reply to this post by Stephan Eggermont-3

Guillermo wrote:
>Maybe you can use a -completely separate- pre-parser? :)
>
>It takes the input with the pre processor directives, and answers a new
>processed string which the original parser will handle?.

Yes, I guess so. I'm fighting a bit with PetitParser, wondering if the traditional
style of building parsers wouldn't be faster. But that might be just about trying
something new. I like the tests, the separate lexicon, syntax and semantics
subclassing not so much better than preprocessing, scanning, parsing.
I definitely don't like having 80 productions in a class (growing to 300, not
sure how to grow over the max nr of instVars ). Is there an array or dictionary
based PPCompositeParser?

Stephan
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Hannes Hirzel

Re: PetitParser handling preprocessor directives?

On 9/14/12, Stephan Eggermont <[hidden email]> wrote:

> Guillermo wrote:
>>Maybe you can use a -completely separate- pre-parser? :)
>>
>>It takes the input with the pre processor directives, and answers a new
>>processed string which the original parser will handle?.
>
> Yes, I guess so. I'm fighting a bit with PetitParser, wondering if the
> traditional
> style of building parsers wouldn't be faster. But that might be just about
> trying
> something new. I like the tests, the separate lexicon, syntax and semantics
>
> subclassing not so much better than preprocessing, scanning, parsing.
> I definitely don't like having 80 productions in a class

I put them into into method categories and that works very fine for me.

(growing to 300,
> not
> sure how to grow over the max nr of instVars ).

I assume it is not possible to have more than 255 rules in a class but
I have not tried this limit yet.

But you can start combining parser as I understand. I have not done
this either, so I would appreciate to be pointed to an example.

--Hannes

Is there an array or
> dictionary
> based PPCompositeParser?
>
> Stephan
> _______________________________________________
> Moose-dev mailing list
> [hidden email]
> https://www.iam.unibe.ch/mailman/listinfo/moose-dev
>
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NorbertHartl

Re: PetitParser handling preprocessor directives?

Am 14.09.2012 um 14:35 schrieb H. Hirzel <[hidden email]>:

> On 9/14/12, Stephan Eggermont <[hidden email]> wrote:
>> Guillermo wrote:
>>> Maybe you can use a -completely separate- pre-parser? :)
>>>
>>> It takes the input with the pre processor directives, and answers a new
>>> processed string which the original parser will handle?.
>>
>> Yes, I guess so. I'm fighting a bit with PetitParser, wondering if the
>> traditional
>> style of building parsers wouldn't be faster. But that might be just about
>> trying
>> something new. I like the tests, the separate lexicon, syntax and semantics
>>
>> subclassing not so much better than preprocessing, scanning, parsing.
>> I definitely don't like having 80 productions in a class
>
> I put them into into method categories and that works very fine for me.
>
> (growing to 300,
>> not
>> sure how to grow over the max nr of instVars ).
>
> I assume it is not possible to have more than 255 rules in a class but
> I have not tried this limit yet.
>

I experienced that limit and it is 254 instance variables.

> But you can start combining parser as I understand. I have not done
> this either, so I would appreciate to be pointed to an example

In order to combine parsers you need separate grammar parts that can be combined with a single rule. I think this can be a heavy task if you have a huge grammar and you like to split it into parts. I tried something by having delegating parsers. Meaning putting productions in separate classes and delegate to the parsers inside a production rule. After a while I started to dislike the approach and got rid of the separate classes again. Instead I compacted the rules a bit. Rules that were really close to each other I have combined in one method having the individual rules in temporary variables. Until now I didn't find any better approach. If the project is huge and a lot of extra complexity is ok then using Lukas' approach in Helvetia would be feasible. By introducing a separate smalltalk parser the accesses to instance variables are mapped onto a dictionary. This way the limit isn't there.

Norbert

> --Hannes
>
> Is there an array or
>> dictionary
>> based PPCompositeParser?
>>
>> Stephan
>> _______________________________________________
>> Moose-dev mailing list
>> [hidden email]
>> https://www.iam.unibe.ch/mailman/listinfo/moose-dev
>>
> _______________________________________________
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