@node Grand LilyPond Input Syntax Standardization (GLISS)
@section Grand LilyPond Input Syntax Standardization (GLISS)
+@subheading Summary
+
+@itemize
+@item
+Start: sortly after 2.14 comes out, which is currently estimated
+to happen in January 2011.
+
+@item
+Length: 6-12 months. We're not going to rush this.
+
+@item
+Goal: define an input which we commit to being
+machine-updateable for the forseeable future. Any future patches
+which change the syntax in a non-convert-ly-able format will be
+rejected. (subject to the limitations, below)
+Once this is finished, we will release lilypond 3.0.
+
+@end itemize
+
+
+@subheading The Problem
+
+One of the biggest complaints people have with lilypond -- other
+than silly thing like "there's no gui" -- is the changing syntax.
+Now, inventing a language or standards is difficult. If you set
+it in stone too soon, you risk being stuck with decisions which
+may limit matters. If you keep on updating the syntax,
+interaction with older data (and other programs!) becomes complex.
+
+@subheading Scope and Limitations
+
+@itemize
+@item
+tweaks will not be included. Anything with \override, \set,
+\overrideProperty, \tweak, \revert, \unset... including even those
+command names themselves... is still fair game for NOT_SMART
+convert-ly updates.
+
+@item
+other than that, everything is on the table. Is it a problem to
+have the tagline inside \header? What should the default behavior
+of \include be? When we abolish \times, do we move to \tuplet 3:2
+or \tuplet 2/3 or what (for typical triplets in 4/4 time)?
+
+@item
+we need to get standards for command names. This will help users
+remember them, and reduce the options for future names (and
+potential renamings later on). \commandOn and \commandOff seem to
+work well (should we *always* have an Off command?), but what
+about the "command" part? Should it be \nounVerbOn, or
+\verbNounOn ? Or \verbNotesWithExtraInformationOn ?
+
+@item
+we need standards for the location of commands. Ligature
+brackets, I'm looking at you. (non-postfix notation must die!)
+
+@item
+this Grand Project doesn't affect whether we have a 2.16 or not.
+The main problem will be deciding what to do (with a bit of
+messiness anticipated for \tuplet); we should definitely release a
+2.16 before merging _any_ of these changes.
+
+@item
+we obviously can't /guarantee/ that we'll /never/ make any
+non-convert-ly changes in the basic format. But we *can*
+guarantee that such changes would force lilypond 4.0, and that we
+would only do so for overwhelmingly good reasons.
+
+@end itemize
+
+@subheading Workflow
+
+@itemize
+@item
+We're going to have lots and lots of emails flying around. The
+vast majority won't really fit into either -devel or -user, so
+we'll use a list devoted to syntax issues.
+
+@item
+Once we have a serious proposal that gained general acceptance
+from the separate syntax mailing list, I'll bring it to -devel.
+We're not going to make any changes without discussing it on
+-devel, but if we're going to have huge threads about English
+grammar and silly ideas, and I don't want to clutter up -devel.
+Once whatever chaotic silliness on the syntax list is settled
+down, I'll bring the ideas to -devel.
+
+@item
+as with GDP, I'll moderate the discussion. Not as with mailist
+moderation, but rather by introducing issues at specific times.
+We don't want a free-for-all discussion of all parts of the syntax
+at once; nothing will get resolved.
+
+@item
+Whenever possible, we'll decide on policies at the highest level
+of abstraction. For example, consider \numericTimeSignature,
+\slurUp, \xNotesOn, \startTextSpan, and \verylongfermata. One of
+them starts with the name of the notation first (slur). One has
+an abbreviation (x instead of cross). One has the verb at the end
+(On), another has it at the beginning (start). The adjective can
+come at the beginning (numeric, x) or end (Up). Most are in
+camelCase, but one isn't (verylongfermata).
+
+@item
+Instead of arguing about each individual command, we'll decide on
+abstract questions. Should each command begin the notation-noun,
+or the verb? Should all commands be in camelCase, or should we
+make everything other than articulations in camelCase but make
+articulations all lower-case? Are abbreviations allowed?
+
+@item
+Once we've answered such fundamental questions, most of the syntax
+should fall into place pretty easily. There might be a few odd
+questions left ("is it a span, or a spanner?"), but those can be
+settled fairly quickly.
+
+@end itemize
+
+@subheading Implementation
+
+Nothing until the project is finished, then we declare the next
+stable release (2.16.0 or 2.18.0 ?) to be the final 2.x version,
+release it, then apply all the GLISS syntax changes and start
+testing a beta for 3.0 a week or two later.
+
+@subheading Discussion
+
+Don't respond to any of the specifics yet. Yes, we all have our
+pet irritations (like "what's up with \paper and \layout?!").
+There will be plenty of time to discuss them once GLISS starts.
+
+That said, we have a list of specific items that people really
+wanted to have written down. See @ref{Specific GLISS issues}.
+
+@menu
+* Specific GLISS issues::
+@end menu
+
+
+@node Specific GLISS issues
+@subsection Specific GLISS issues
+
+@itemize
+@item
+add regtests for every piece of syntax (not one-command-per-file,
+but making a few files which, between them, use every single piece
+of syntax.) This is a great test for convert-ly.
+
+@item
+should GLISS cover suggested conventions? (indentation,
+one-bar-per-line, etc -- the kind of stuff we list for the
+lilypond formatting in the docs ?)
+
+@item
+how much (if any) syntactic sugar should we add? i.e.
+@example
+ \instrumentName #'foo
+% instead of
+ \set Staff.instrumentName
+@end example
+? Carl: maybe yes, Neil: no. (for example, it fails for
+pianostaff)
+
+@item
+the values that are used as arguments to common used overrides.
+Sometimes they are a symbol (e.g. #'around), sometimes a
+predefined variable referring to a Scheme value or object (e.g.
+#LEFT, #all-visible ). The main trouble is that for novice users
+it is not clear when there should be an apostrophe and when not.
+
+@item
+When do we need -\command and when is it just \command ?
+
+
+@item
+Command-line options to the lilypond binary. -dfoo counts as a
+tweak; we won't be trying to pin those down.
+
+@item
+@verbatim
+\layout {
+ \context { \Score
+% vs.
+\layout {
+ \context {
+ \Score
+@end verbatim
+
+@item
+If would be pedagogically simpler to realize this difference if
+the syntax was separate if you define a context from scratch (as
+is the case with \RemoveEmptyStaffContext) or if it's defined by
+adding onto an existing context. For example, a syntax like
+
+@verbatim
+\context{
+ % Copy the current settings of the Staff context:
+ \use Staff
+ % do whatever additional settings
+}
+%%% could be used to distinguish from
+\context{
+ % Take settings from a variable:
+ \Variable
+ % do whatever additional settings
+}
+
+%%% and
+
+\context{
+ % Start from scratch:
+ \type ...
+ \name ...
+ \consists ...
+ ...
+}
+@end verbatim
+
+@item
+Capitalization of identifiers: \VoiceOne ?
+
+@item
+@verbatim
+%%% Allow
+{ music expression } * 4
+%%% instead of
+\repeat unfold 4 { music expression }
+@end verbatim
+
+? patch here:
+@uref{http://lists.gnu.org/archive/html/lilypond-devel/2010-04/msg00467.html}
+
+@item
+Personally, I find it easier to understand when there's a repeated
+8 in the half-bar position; it's much easier to see that you have
+two groups of 4:
+
+@example
+c8 c c c c8 c c c
+%%% instead of one group of eight:
+c8 c c c c c c c
+@end example
+
+@item
+trivially simple bar-lines:
+
+c1 | c1 |
+
+encourage, allow, or discourage, or disallow?
+
+@item
+indentation of \\ inside a @{@} construct.
+
+
+@item
+barline checks at the end of line should be preceded by at least 2
+spaces? barline checks should line up if possible (i.e. if you
+can use less than 4, 8, X empty spaces before a barline check to
+make them line up?)
+
+@item
+Why doesn't \transpose respect \relative mode?
+
+
+@item
+on \score vs. \new Score
+
+But in the light of a consistent syntax and semantic, I see no
+reason (from the users POV) to disallow it. After all, the real
+top-level context is a \book @{@}, isn't it, and I don't see a point
+in disallowing a \new Score construct just like \new Staff.
+
+From a syntactical POV, I see the following pros for \new Score:
+- You can write \with @{ ... @} for every other context but \Score,
+which (for consistency) should also work with \new Score.
+- When there's a \new Foo Bar, there's also a \context Foo Bar,
+ which makes the same as a parallel instantiation of all Bar's.
+- [Quoting Rune from
+@uref{http://www.mail-archive.com/lilypond-devel@@gnu.org/msg14713.html}
+ "I know that the \score-statement is a syntactical construct,
+but I think it would be nice to hide this fact from the users. I
+think we could make the use of score-block much more intuitive if
+changing the syntax to \new \Score and adding an implicit
+sequential-statement to the score."
+
+
+@item
+Discussion on
+http://code.google.com/p/lilypond/issues/detail?id=1322
+about \new vs. \context.
+
+
+@item
+Let users add their own items to the parser? comment 11 on:
+http://code.google.com/p/lilypond/issues/detail?id=1322
+
+
+@end itemize
@node Unsorted policies
projects / lilypond.git / commitdiff