> >> > (modify-syntax-entry ?\= "_ b12" st) ; comment start == > >> > >> Yes, it seems the problem is that your 2-char comment > sequence is made > >> of symbol-chars, so there are cases where the code does > things like "oh, > >> here's a symbol, let's skip it" without checking whether > some of the > >> chars that compose the symbol happen to also be a comment-marker. > >> > >> Does your = char really need to have "symbol" syntax (i.e. "_") or > >> could it have punctuation syntax instead (i.e. ".") ? > > > Punctuation syntax seems to cause all kinds of problems. The = > > character is commonly used as the first character in in > > filenames. > > But does it matter in such a case whether it has punctuation syntax or > symbol syntax? Do you also give symbol syntax to the / > directory separator as well?
A / is an illegal character in any part of a filename on this system. In this language / / are most often seen as paired delimiters. > > It's also part of several operators such as := and ':=' and > '=:' which > > would behave quite oddly without proper syntax. > > Traditionally, punctuation syntax has been used specifically > for things like > the above. So, I'd say that punctuation *is* the proper > syntax. If you use > symbol syntax for those chars, things like M-C-f risk skipping over > "foo:=bar" in "foo:=bar + 1", rather than just skipping over "foo". [#set foo [bar]] and [#set foo [#compute bar + 1]] would be required to accomplish the operations your examples seem to describe. If I see ':=' in this language I would almost certainly want it treated as a word. > > > It sounds like you are saying it might be a problem to fix the code. > > Yes: it might take a bit of work; it risks slowing down syntax-based > operations in all buffers; and it could introduce bugs in > other languages > where the current behavior is closer to what we want (after > all, if you > define your language using lex and you say that a symbol can > be [a-z=_]+ > and a comment starter is ==, your lexer will take `foo==' to > be a symbol > and won't see the comment starter in it). In this language == always begins a comment no matter where it is found unless a ~ precedes it. There are no exceptions. > > The current behavior is buggy (it doesn't behave consistently between > things like forward-sexp, backward-sexp, and parse-partial-sexp). > > But before someone can convince me to try and fix these bugs, > they should > first make a good case that the way they setup their > syntax-tables is well > thought out. > If the fact that the problem exists reflects the standard by which `well thought out' is measured you're being a pushover. I suppose, since it's possible for me to work around this problem by using syntactic-keywords to handle the comments I would prefer problems for which there are no workarounds be addressed first. If it will remain this way for any length of time though, I do think it should be documented somewhere. Even if only on a known problems list. _______________________________________________ Emacs-devel mailing list Emacs-devel@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-devel
