[antlr-interest] .g vs .g4

Stuart Dootson stuart.dootson at gmail.com
Tue Nov 8 02:20:50 PST 2011


How about doing what GCC does, and provide a flag to allow hte user to
specify the language being processed?

In gcc, I could do:

gcc -x c++ test.c

To compile test.c as with the C++ compiler. I could also do

gcc -x f77 test.c

to compile test.c using the Forrtan 77 compiler...

The default, however, is '-x none', which means 'look at the filename
extension to determine the compiler to use'...

Just a suggestion...

Stuart Dootson

On 6 November 2011 17:55, Terence Parr <parrt at cs.usfca.edu> wrote:

> Hi Eric,I think we are going to allow .g as well.   Rather than a property
> in the grammar file itself that identifies the version, I think we were
> going to use the file extension for this reason. all v3 grammars will be .g
> and people building v4 grammar should name them .g4
> Ter
> On Nov 6, 2011, at 9:29 AM, Eric wrote:
>
> >
> >
> > On Sun, Nov 6, 2011 at 12:22 PM, Terence Parr <parrt at cs.usfca.edu>
> wrote:
> > Hi, Sam Harwell and I are talking about the file extension for new ANTLR
> 4. We think it makes good sense to use .g4 to distinguish the new grammars.
> They're mostly compatible except that there is no need for syntactic
> predicates and .g4 allows immediate left recursion. I think it will reduce
> confusion about what version of ANTLR is necessary to compile a grammar.
> >
> > Ter
> >
> > List: http://www.antlr.org/mailman/listinfo/antlr-interest
> > Unsubscribe:
> http://www.antlr.org/mailman/options/antlr-interest/your-email-address
> >
> >
> > Hi Ter,
> >
> > Will v4 require the file type to be .g4, or will it accept .g and .g4?
> >
> > My preference is for .g4 only.
> >
> > Also, will there be a property in the grammar file that identifies the
> minimum version or required version. I think it would help for obvious
> reasons such as when a user post a grammar needing help or an example
> grammar is given.
> >
> > Thanks, Eric
> >
> >
>
>
> List: http://www.antlr.org/mailman/listinfo/antlr-interest
> Unsubscribe:
> http://www.antlr.org/mailman/options/antlr-interest/your-email-address
>


More information about the antlr-interest mailing list