#5067 Add lilypond version predicates/operators

[Urs Liska]

Add lilypond version predicates/operators

This set of predicates/operators compares a given reference version
to the LilyPond version that is currently being executed.
This makes it possible to implement "version switches" to write
(library) code that is compatible over syntax changes.

NOTE: I'm not sure where (and if) this should be documented.
Please make suggestions

http://codereview.appspot.com/317270043

[Urs Liska]

Some example code for the feature:

%%%%
\version "2.19.54"

#(ly:message "LilyPond > 2.19.5? ~a" (lilypond>? "2.19.5"))

#(cond
  ((lilypond>? '(2 18))
   (ly:message "Running development version"))
  ((lilypond=? '(2 18))
   (ly:message "Running latest stable version"))
  (else (ly:message "Running ancient version")))

functionSwitch =
#(define-void-function (parser location)()
   (if
    (lilypond>? "2.19.21")
    (ly:parser-include-string "#(display \"Included string\")")
    (ly:parser-include-string parser "#(display \"Included string\")")))

\functionSwitch
%%%

Of course this will not actually work with older versions because they
don't have the functions
built in. But it serves to demonstrate the use case for future syntax
changes

Am 10.02.2017 um 09:04 schrieb Urs Liska:

---

[issues:#5067]
https://sourceforge.net/p/testlilyissues/issues/5067/ Add lilypond
version predicates/operators

Status: Started
Created: Fri Feb 10, 2017 08:04 AM UTC by Urs Liska
Last Updated: Fri Feb 10, 2017 08:04 AM UTC
Owner: nobody

Add lilypond version predicates/operators

This set of predicates/operators compares a given reference version
to the LilyPond version that is currently being executed.
This makes it possible to implement "version switches" to write
(library) code that is compatible over syntax changes.

NOTE: I'm not sure where (and if) this should be documented.
Please make suggestions

http://codereview.appspot.com/317270043

---

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--
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[Anonymous]

Passes, make make check and a full make doc.

[Anonymous]

Patch on countdown for February 17th.

[Urs Liska]

Reflect discussions.

http://codereview.appspot.com/317270043

[Urs Liska]

Stub for trying out the functions:

#(format #t ">: ~a\n" (version-compare? '(2 19 5) = '(2 18 0)))

It should work with all combinations of operators and combinations of
list lengths

[Anonymous]

Passes make, make check and a full make doc.

[Urs Liska]

Lexicographic comparison and ly:version? wrapper

http://codereview.appspot.com/317270043

[Urs Liska]

Test code for latest patch set:

#(format #t "Three elements (current version 2.19.54):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 19 54))
   (ly:version? >= 2 19 54)
   (ly:version? = 2 19 54)
   (ly:version? <= 2 19 54))

#(format #t "Three elements (future version 2.19.57):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 19 57))
   (ly:version? >= 2 19 57)
   (ly:version? = 2 19 57)
   (ly:version? <= 2 19 57))

#(format #t "Three elements (earlier version 2.19.10):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 19 10))
   (ly:version? >= 2 19 10)
   (ly:version? = 2 19 10)
   (ly:version? <= 2 19 10))

#(format #t "Two elements (2 19):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 19))
   (ly:version? >= 2 19)
   (ly:version? = 2 19)
   (ly:version? <= 2 19))

#(format #t "Two elements (2 18):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 18))
   (ly:version? >= 2 18)
   (ly:version? = 2 18)
   (ly:version? <= 2 18))

#(format #t "Two elements (2 20):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2 20))
   (ly:version? >= 2 20)
   (ly:version? = 2 20)
   (ly:version? <= 2 20))

#(format #t "One element (2):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(2))
   (ly:version? >= 2)
   (ly:version? = 2)
   (ly:version? <= 2))

#(format #t "One element (3):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(3))
   (ly:version? >= 3)
   (ly:version? = 3)
   (ly:version? <= 3))

#(format #t "One element (1):\n> : ~S, >= : ~S\n= : ~S, <= : ~S\n"
   (ly:version? > '(1))
   (ly:version? >= 1)
   (ly:version? = 1)
   (ly:version? <= 1))

[Anonymous]

Passes make, make check and a full make doc.

[Anonymous]

Patch on countdown for February 20th.

[Urs Liska]

Rename secondary function after discussion

http://codereview.appspot.com/317270043

[Urs Liska]

Fix omission of previous patch set

http://codereview.appspot.com/317270043

[Anonymous]

passes make, make check and a full make doc.

[Anonymous]

Leaving this on review, David has some comment in Rietveld.

[Urs Liska]

Am 2017-02-20 14:30, schrieb pkx166h:

Leaving this on review, David has some comment in Rietveld.

This is not necessary. David's last comments crossed with my patch set 4
where I took back my doubts about the naming. In fact I had renamed the
function to David's original suggestion.

[Urs Liska]

Limit ly:version? to number list (as suggested by Paul)

http://codereview.appspot.com/317270043

[Anonymous]

Passes make, make check and a full make doc.