Re: [cedet-semantic] simple bovine example of "A Rule must return a single tag-line list!"

[Eric M. L. <er...@si...>]

Hi,

  Emacs says I forgot to answer you email.  My apologies!

  The answer to the "A Rule must return a single tag-line list" is
that the purpose of the grammar is to create a list of tags.  The
"article" rule should, at a minimum, look like this:

article
   : environment-declaration text-proper
     (TAG "somename" 'tagclassimadeup :optionaldetail "somethingelse")
   ;

The declaration of the tag can occur anywhere in the grammar, and each
production passes the value up until it reaches your %start token.

See the "Optional Lambda Expression" section in the bovine.info file.

You might be able to put a nil in there too.  I don't recall the
specifics.

Sorry for the delay.
Eric

>>> Jesse Alama <al...@st...> seems to think that:
>After fooling around with a bovine grammar I'm working on, I managed
>to find a simple example of a grammar which, when I call `bovinate',
>give me the error "A Rule must return a single tag-line list!".
>
>Here's the bovine file:
>
>----------------------------------------------------------------------
>%package pretty-trivial
>
>%language-mode my-trivial-mode
>%start article
>
>%keyword ENVIRON        "environ"
>%put     ENVIRON summary
>%keyword BEGIN          "begin"
>%put     BEGIN summary
>
>%%
>
>article
>  : environment-declaration text-proper
>  ;
>
>environment-declaration
>  : ENVIRON
>  ;
>
>text-proper
>  : BEGIN
>  ;
>
>%%
>----------------------------------------------------------------------
>
>Then here's the package file:
>
>----------------------------------------------------------------------
>(require 'semantic)
>(require 'pretty-trivial)
>(require 'backquote)
>
>;; Depending on what elements you include specialized support for
>(eval-when-compile
>  (require 'semantic-ctxt)
>  (require 'semantic-imenu)
>  (require 'document)
>  (require 'senator))
>
>;;; Code:
>
>;; Create a lexical analyzer for your language.  You can use
>;; both the provided analyzers, and your own custom analyzers
>;; that let you take short-cuts in your language.
>
>;; Define the lexial analyzer
>(define-lex semantic-trivial-lexer
>  "Lexical Analyzer for trivial articles."
>  semantic-lex-ignore-whitespace
>  semantic-lex-ignore-newline
>  semantic-lex-number
>  semantic-lex-symbol-or-keyword
>  semantic-lex-paren-or-list
>  semantic-lex-close-paren
>  semantic-lex-ignore-comments
>  semantic-lex-punctuation
>  semantic-lex-default-action)
>
>(defun semantic-default-trivial-setup ()
>  "Set up a buffer for semantic parsing of the skeleton language."
>  (pretty-trivial--install-parser)
>  (setq semantic-lex-analyzer #'semantic-trivial-lexer)
>  )
>----------------------------------------------------------------------
>Evaluate the package file generated by the bovine grammar, then the
>above file.  Visit a buffer whose content is
>----------------------------------------------------------------------
>environ
>
>begin
>----------------------------------------------------------------------
>Then evaluate `semantic-default-trivial-setup' and then evaluate
>`semantic-new-buffer-fcn'.  I immediately get the error
>
>  A Rule must return a single tag-line list!
>
>What does that error mean and why is it coming up in this example?
>
>Thanks,
>
>Jesse
>