Re: What is the point of \on-the-fly ?
On 06/13/2017 11:16 AM, David Kastrup wrote: (define-markup-command bla) does not define bla, but rather bla-markup, make-bla-markup and bits and pieces used for signatures and the markup macro. Even then, creating music functions on the fly _and_ using them requires use of $(define-music-function ...) since #(define-music-function ...) does not call the generated music function (would be hard assigning a music function if it got called right away...). Ah ok, thanks for the explanation. (I need to brush up on my $ vs #.) I actually just proposed an issue where you _can_ call markup functions on the fly when defined properly. Sounds good. This is the $ one. But the process of assigning a markup command with all that it entails cannot be done in the same manner. Since we can generate markup commands "on the fly" with \markup ... \etc, assigning them in a manner corresponding to define-markup-command might be nice. I suggested \markup bla = ... for it without being all too clear about whether this implied \markup mode, allowing for \markup bla = \bold \large \etc rather than \markup bla = \markup \bold \large \etc There were no real comments (and I am fuzzy on the details of the ensuing non-discussion as far as I remember it) so this proposal petered out. Hmm, I must have missed this, but sounds promising. -Paul ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
Re: What is the point of \on-the-fly ?
Paul writes: > On 06/12/2017 01:00 AM, David Kastrup wrote: > >> The use case is similar to that of lambda: creating a procedure on the >> fly without giving it a name. > > Ah, got it. Then makes sense to avoid having to use on-the-fly, by > converting those named on-the-fly procedures into actual markup > commands. > > Just thinking out loud, but if define-markup-command worked like > define-music-function and friends (i.e. like lambda) so that they > returned a procedure, like this: > > command-name = #(define-markup-command (layout props args...) ... > > (define command-name (define-markup-command (layout props args...) ... > > Rather than the current form: > > (define-markup-command (command-name layout props args...) ... > > Would that remove the need for on-the-fly or am I missing something? > I'm sure that would not be a trivial change -- again just thinking out > loud. (define-markup-command bla) does not define bla, but rather bla-markup, make-bla-markup and bits and pieces used for signatures and the markup macro. Even then, creating music functions on the fly _and_ using them requires use of $(define-music-function ...) since #(define-music-function ...) does not call the generated music function (would be hard assigning a music function if it got called right away...). I actually just proposed an issue where you _can_ call markup functions on the fly when defined properly. But the process of assigning a markup command with all that it entails cannot be done in the same manner. Since we can generate markup commands "on the fly" with \markup ... \etc, assigning them in a manner corresponding to define-markup-command might be nice. I suggested \markup bla = ... for it without being all too clear about whether this implied \markup mode, allowing for \markup bla = \bold \large \etc rather than \markup bla = \markup \bold \large \etc There were no real comments (and I am fuzzy on the details of the ensuing non-discussion as far as I remember it) so this proposal petered out. -- David Kastrup ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
Re: What is the point of \on-the-fly ?
On 06/12/2017 01:00 AM, David Kastrup wrote: The use case is similar to that of lambda: creating a procedure on the fly without giving it a name. Ah, got it. Then makes sense to avoid having to use on-the-fly, by converting those named on-the-fly procedures into actual markup commands. Just thinking out loud, but if define-markup-command worked like define-music-function and friends (i.e. like lambda) so that they returned a procedure, like this: command-name = #(define-markup-command (layout props args...) ... (define command-name (define-markup-command (layout props args...) ... Rather than the current form: (define-markup-command (command-name layout props args...) ... Would that remove the need for on-the-fly or am I missing something? I'm sure that would not be a trivial change -- again just thinking out loud. -Paul ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
Re: What is the point of \on-the-fly ?
Thomas Morley writes: > 2017-06-11 15:08 GMT+02:00 David Kastrup : >> >> \on-the-fly gets as first argument a function that it calls on the >> second argument as if the first argument was actually a markup command. >> >> Why not make the first argument actually a markup command? >> >> It would appear that we are mostly talking about a closed set here >> anyway. So why >> >> \markup \on-the-fly #(on-page 3) "blabla" >> >> instead of >> >> \markup \on-page #3 "blabla" >> >> ? Where is the point in this particular obfuscation? >> >> -- >> David Kastrup > > on-the-fly is one (of two) markup-(list-)commands in > define-markup-commands.scm which takes a procedure as argument (the > other is map-markup-commands). This procedure needs to have three > arguments: layout, props and the one which is actually worked on. > > I desperately tried to find such a procedure, being sufficiently > different from markup-(list-)-commands. To no avail. > > So I'd vote for dropping on-the-fly entirely. (Unless somebody know a > good use-case) The use case is similar to that of lambda: creating a procedure on the fly without giving it a name. But most of the current uses of \on-the-fly are on a procedure _with_ a name. > Ofcourse several procedures in titling-init.ly would need to become > markup-commands. My guess is that this might have been an emergency measure because of problems with the scopes/modules of markups (since the usual \on-the-fly suspects are in the \paper module). But I think that this may have been solved in the mean time. > map-markup-commands from define-markup-commands.scm needs to be > changed as well. And regtests and docs... I don't think there's anything wrong with keeping \on-the-fly . But requiring its use does not seem like doing people a favor. -- David Kastrup ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
Re: What is the point of \on-the-fly ?
2017-06-11 15:08 GMT+02:00 David Kastrup : > > \on-the-fly gets as first argument a function that it calls on the > second argument as if the first argument was actually a markup command. > > Why not make the first argument actually a markup command? > > It would appear that we are mostly talking about a closed set here > anyway. So why > > \markup \on-the-fly #(on-page 3) "blabla" > > instead of > > \markup \on-page #3 "blabla" > > ? Where is the point in this particular obfuscation? > > -- > David Kastrup on-the-fly is one (of two) markup-(list-)commands in define-markup-commands.scm which takes a procedure as argument (the other is map-markup-commands). This procedure needs to have three arguments: layout, props and the one which is actually worked on. I desperately tried to find such a procedure, being sufficiently different from markup-(list-)-commands. To no avail. So I'd vote for dropping on-the-fly entirely. (Unless somebody know a good use-case) Ofcourse several procedures in titling-init.ly would need to become markup-commands. map-markup-commands from define-markup-commands.scm needs to be changed as well. And regtests and docs... Cheers, Harm ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
What is the point of \on-the-fly ?
\on-the-fly gets as first argument a function that it calls on the second argument as if the first argument was actually a markup command. Why not make the first argument actually a markup command? It would appear that we are mostly talking about a closed set here anyway. So why \markup \on-the-fly #(on-page 3) "blabla" instead of \markup \on-page #3 "blabla" ? Where is the point in this particular obfuscation? -- David Kastrup ___ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
