I understand the basic parsing for the majority of common cases can be done fairly easily, but this seems rather error-prone for something that will eventually be moving a machine. I am hoping to build something that is more robust for handling, e.g. inline comments and all of the other special cases present in the specification. I then want to expand it further to perform validation and normalization of the gcode, splitting lines, etc.
There is seemingly a grammar for the language that could be used to http://www.isd.mel.nist.gov/documents/kramer/RS274VGER_11.pdf around page 60. Unless something like this exists, my plan would be to use a parser generator like antlr to build a parser using that grammar, and then implement the validation on top of that, verifying using for instance the modal group rules here: http://www.linuxcnc.org/docview/html/gcode_overview.html And ordering things per the actual order of execution rules. My hope is that then I will be able to safely use a simple text-based transformation against the output of this process after the file has been parsed, normalized and validated. I am hoping someone at some point did most of that work, though, in a way that can be used from python in EMC2. Hope that helps clarify, Scott On Sat, Jan 21, 2012 at 1:10 PM, Ed Nisley <ed.08.nis...@pobox.com> wrote: > On Sat, 2012-01-21 at 12:44 -0600, Jon Elson wrote: > > Every numeric value is preceded by a letter telling what it is. > > Except in the wonderful world of RepRap, wherein they're now > (contemplating?) dual-extruder "G-Code" with multiple numeric values > after the E axis to mix / simultaneously extrude multiple materials: > > http://reprap.org/wiki/G-code#M160:_Number_of_mixed_materials > > The E axis must then absorb a linear "distance" of filament, plus the > mix fractions for each material. > > The RepRap dialect seems to be diverging fairly rapidly from what the > LinuxCNC parser understands; in particular, their myriad M codes look > like a problem. > > -- > Ed > http://softsolder.com > > > > > ------------------------------------------------------------------------------ > Try before you buy = See our experts in action! > The most comprehensive online learning library for Microsoft developers > is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, > Metro Style Apps, more. Free future releases when you subscribe now! > http://p.sf.net/sfu/learndevnow-dev2 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
