1 @c -*- coding: utf-8; mode: texinfo; -*-
4 Translation of GIT committish: FILL-IN-HEAD-COMMITTISH
6 When revising a translation, copy the HEAD committish of the
7 version that you are working on. For details, see the Contributors'
8 Guide, node Updating translation committishes..
14 @node Updating files with convert-ly
15 @chapter Updating files with @command{convert-ly}
17 @cindex Updating a LilyPond file
20 The LilyPond input syntax is routinely changed to simplify it or improve
21 it in different ways. As a side effect of this, the LilyPond interpreter
22 often is no longer compatible with older input files. To remedy this,
23 the program @command{convert-ly} can be used for upgrading files
24 to newer versions of LilyPond.
27 * Why does the syntax change?::
28 * Invoking convert-ly::
29 * Command line options for convert-ly::
30 * Problems running convert-ly::
31 * Manual conversions::
35 @node Why does the syntax change?
36 @section Why does the syntax change?
39 @cindex updating old input files
41 The LilyPond input syntax occasionally changes. As LilyPond
42 itself improves, the syntax (input language) is modified
43 accordingly. Sometimes these changes are made to make the input
44 easier to read and write or sometimes the changes are made to
45 accommodate new features of LilyPond.
47 For example, all @code{\paper} and @code{\layout} property names
48 are supposed to be written in the form @code{first-second-third}.
49 However, in version 2.11.60, we noticed that the
50 @code{printallheaders} property did not follow this convention.
51 Should we leave it alone (confusing new users who must deal with
52 an inconsistent input format), or change it (annoying old users
53 with existing scores)? In this case, we decided to change the
54 name to @code{print-all-headers}. Fortunately, this change can be
55 automated with our @command{convert-ly} tool.
57 Unfortunately, @command{convert-ly} cannot handle all input changes.
58 For example, in LilyPond 2.4 and earlier, accents and non-English
59 letters were entered using LaTeX -- displaying the French word for
60 Christmas was entered as @code{No\"el}. But in LilyPond
61 @c keep "-matching straight in fancy editors
62 2.6 and above, the special @code{ë} must be entered directly into
63 the LilyPond file as an UTF-8 character. @command{convert-ly} cannot
64 change all the LaTeX special characters into UTF-8 characters; you
65 must manually update your old LilyPond input files.
67 The conversion rules of @command{convert-ly} work using text pattern
68 matching and replacement rather than a thorough understanding of
69 LilyPond. This has several consequences:
72 The reliability of the conversion depends on the quality of each
73 applied rule set and on the complexity of the respective change.
74 Sometimes conversions may require manual fixes, so the old version
75 should be kept available for comparison.
77 Only conversions to newer formats are possible: there are no rule
78 sets for downgrading. So the main working copy of a LilyPond file
79 should only be upgraded when older versions of LilyPond no longer
80 need to be supported. Version control systems such as Git might
81 help with maintaining multiple versions.
83 LilyPond and Scheme themselves are quite robust against creatively
84 placed and omitted spaces, but the rules used by
85 @command{convert-ly} tend to make some stylistic assumptions.
86 Following the style used in the manuals is the safest bet for
87 painless upgrades, particularly as the manuals themselves are
88 upgraded using @command{convert-ly}.
92 @node Invoking convert-ly
93 @section Invoking @command{convert-ly}
95 @command{convert-ly} uses @code{\version} statements in the input
96 file to detect the old version number. In most cases, to upgrade
97 your input file it is sufficient to run
100 convert-ly -e myfile.ly
104 in the directory containing the file. This will upgrade
105 @file{myfile.ly} in-place and preserve the original file in
108 @warning{@command{convert-ly} always converts up to the last
109 syntax change handled by it. This means that the @code{\version}
110 number left in the file is usually lower than the version of
111 @command{convert-ly} itself.}
113 To convert all the input files in a directory together use
119 Alternatively, if you want to specify a different name for the
120 upgraded file, preserving the original file and name unchanged,
124 convert-ly myfile.ly > mynewfile.ly
127 The program will list the version numbers for which conversions
128 have been made. If no version numbers are listed the file is
131 MacOS@tie{}X users may execute these commands under the menu entry
132 @code{Compile > Update syntax}.
134 Windows users should enter these commands in a Command Prompt
135 window, which is usually found under
136 @code{Start > Accessories > Command Prompt}.
139 @node Command line options for convert-ly
140 @section Command line options for @command{convert-ly}
142 The program is invoked as follows:
145 convert-ly [@var{option}]@dots{} @var{filename}@dots{}
148 The following options can be given:
151 @item -d,--diff-version-update
152 increase the @code{\version} string only if the file has actually
153 been changed. Without this option (or when any conversion has
154 changed the file), the version header reflects the last considered
158 Apply the conversions direct to the input file, modifying it
161 @item -f,--from=@var{from-patchlevel}
162 Set the version to convert from. If this is not set, @command{convert-ly}
163 will guess this, on the basis of @code{\version} strings in the file.
164 E.g. @option{--from=2.10.25}
169 @item -l @var{loglevel}, --loglevel=@var{loglevel}
170 Set the output verbosity to @var{loglevel}. Possible values, in upper
171 case, are @code{PROGRESS} (the default), @code{NONE}, @code{WARNING},
172 @code{ERROR} and @code{DEBUG}.
174 @item -n,--no-version
175 Normally, @command{convert-ly} adds a @code{\version} indicator
176 to the output. Specifying this option suppresses this.
178 @item -s, --show-rules
179 Show all known conversions and exit.
181 @item -t, --to=@var{to-patchlevel}
182 Explicitly set which @code{\version} to convert to, otherwise the
183 default is the most current value. It must be higher than the
187 convert-ly --to=2.14.1 myfile.ly
192 To upgrade LilyPond fragments in texinfo files, use
195 convert-ly --from=@dots{} --to=@dots{} --no-version *.itely
198 To see the changes in the LilyPond syntax between two versions, use
201 convert-ly --from=@dots{} --to=@dots{} -s
205 @node Problems running convert-ly
206 @section Problems running @code{convert-ly}
208 When running convert-ly in a Command Prompt window under Windows
209 on a file which has spaces in the filename or in the path to it,
210 it is necessary to surround the entire input file name with three
211 (!) sets of double quotes:
214 convert-ly """D:/My Scores/Ode.ly""" > "D:/My Scores/new Ode.ly"
217 If the simple @command{convert-ly -e *.ly} command fails because the
218 expanded command line becomes too long, the @command{convert-ly}
219 command may be placed in a loop instead. This example for UNIX
220 will upgrade all @file{.ly} files in the current directory
223 for f in *.ly; do convert-ly -e $f; done;
226 In the Windows Command Prompt window the corresponding command is
229 for %x in (*.ly) do convert-ly -e """%x"""
232 Not all language changes are handled. Only one output option can be
233 specified. Automatically updating scheme and LilyPond scheme
234 interfaces is quite unlikely; be prepared to tweak scheme code
238 @node Manual conversions
239 @section Manual conversions
241 In theory, a program like @command{convert-ly} could handle any
242 syntax change. After all, a computer program interprets the old
243 version and the new version, so another computer program can
244 translate one file into another@footnote{At least, this is
245 possible in any LilyPond file which does not contain scheme. If
246 there is scheme in the file, then the LilyPond file contains a
247 Turing-complete language, and we run into problems with the famous
248 @qq{Halting Problem} in computer science.}.
250 However, the LilyPond project has limited resources: not all
251 conversions are performed automatically. Below is a list of known
257 Doesn't always convert figured bass correctly, specifically things like {<
258 >}. Mats' comment on working around this:
259 To be able to run convert-ly
260 on it, I first replaced all occurrences of '{<' to some dummy like '{#'
261 and similarly I replaced '>}' with '&}'. After the conversion, I could
262 then change back from '{ #' to '{ <' and from '& }' to '> }'.
263 Doesn't convert all text markup correctly. In the old markup syntax,
264 it was possible to group a number of markup commands together within
266 -#'((bold italic) "string")
267 This will incorrectly be converted into
268 -\markup{{\bold italic} "string"}
269 instead of the correct
270 -\markup{\bold \italic "string"}
272 Doesn't handle \partcombine
273 Doesn't do \addlyrics => \lyricsto, this breaks some scores with multiple
276 \magnify isn't changed to \fontsize.
277 - \magnify #m => \fontsize #f, where f = 6ln(m)/ln(2)
278 remove-tag isn't changed.
279 - \applyMusic #(remove-tag '. . .) => \keepWithTag #'. . .
280 first-page-number isn't changed.
281 - first-page-number no => print-first-page-number = ##f
282 Line breaks in header strings aren't converted.
283 - \\\\ as line break in \header strings => \markup \center-align <
284 "First Line" "Second Line" >
285 Crescendo and decrescendo terminators aren't converted.
289 \turnOff (used in \set Staff.VoltaBracket = \turnOff) is not properly
292 \markup{ \center-align <{ ... }> } should be converted to:
293 \markup{ \center-align {\line { ... }} }
294 but now, \line is missing.
296 Special LaTeX characters such as $~$ in text are not converted to UTF8.
298 \score{} must now begin with a music expression. Anything else
299 (particularly \header{}) must come after the music.