lilypond-book robustness: ensure EOL at the end of @verbatim

[lilypond.git] / Documentation / user / scheme-tutorial.itely

diff --git a/Documentation/user/scheme-tutorial.itely b/Documentation/user/scheme-tutorial.itely
index 6d8f33e0f8f285083a8a0ac152fd2ee6d222931f..18f79c2d15bfa021aedd3565c9e8100e91fabaf2 100644 (file)
--- a/Documentation/user/scheme-tutorial.itely
+++ b/Documentation/user/scheme-tutorial.itely
@@ -26,7 +26,25 @@ together.  This section is a very brief overview of entering data in
 Scheme.  If you want to know more about Scheme, see
 @uref{http://@/www@/.schemers@/.org}.
 
-The most basic thing of a language is data: numbers, character
+LilyPond uses the GNU Guile implementation of Scheme, which is
+based on the Scheme @qq{R5RS} standard. If you are learning Scheme
+to use with LilyPond, working with a different implementation (or
+referring to a different standard) is not recommended. Information
+on guile can be found at @uref{http://www.gnu.org/software/guile/}.
+The @qq{R5RS} Scheme standard is located at
+@uref{http://www.schemers.org/Documents/Standards/R5RS/}.
+
+The LilyPond installation also includes the Guile implementation of
+Scheme.  On most systems you can experiment in a Scheme sandbox by
+opening a terminal window and typing @q{guile}.  On some systems,
+notably Windows, you may need to set the environment variable
+@code{GUILE_LOAD_PATH} to the directory @code{../usr/shr/guile/1.8}
+in the LilyPond installation (for the full path to this directory
+see @ref{Other sources of information}).  Alternatively, Windows
+users may simply choose @q{Run} from the Start menu and enter
+@q{guile}.
+
+The most basic concept in a language is data typing: numbers, character
 strings, lists, etc.  Here is a list of data types that are relevant to
 LilyPond input.
 
@@ -70,7 +88,7 @@ respectively.
 
 
 In a music file, snippets of Scheme code are introduced with the hash
-mark @code{#}.  So, the previous examples translated in LilyPond are
+mark @code{#}.  So, the previous examples translated to LilyPond are
 
 @example
 ##t ##f
@@ -81,6 +99,35 @@ is
 a string"
 @end example
 
+Note that LilyPond comments (@code{%} and @code{%@{ %@}}) cannot
+be used within Scheme code.  Comments in Guile Scheme are entered
+as follows:
+
+@example
+; this is a single-line comment
+
+#!
+  This a (non-nestable) Guile-style block comment
+  But these are rarely used by Schemers and never in
+  LilyPond source code
+!#
+@end example
+
+Multiple consecutive scheme expressions in a music file can be
+combined using the @code{begin} operator. This permits the number
+of hash marks to be reduced to one.
+
+@example
+#(begin
+  (define foo 0)
+  (define bar 1))
+@end example
+
+If @code{#} is followed by an opening bracket, @code{(}, as in
+the example above, the parser will remain in Scheme mode until
+a matching closing bracket, @code{)}, is found, so further
+@code{#} symbols to introduce a Scheme section are not required.
+
 For the rest of this section, we will assume that the data is entered
 in a music file, so we add @code{#}s everywhere.
 
@@ -252,22 +299,24 @@ We can use it to create new commands:
 @c Check this is a valid example with skylining
 @c It is - 'padding still works
 
+
 @lilypond[quote,verbatim,ragged-right]
-tempoMark = #(define-music-function (parser location padding marktext)
-                                    (number? string?)
+tempoPadded = #(define-music-function (parser location padding tempotext)
+  (number? string?)
 #{
-  \once \override Score . RehearsalMark #'padding = $padding
-  \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
-  \mark \markup { \bold $marktext }
+  \once \override Score.MetronomeMark #'padding = $padding
+  \tempo \markup { \bold $tempotext }
 #})
 
 \relative c'' {
-  c2 e
-  \tempoMark #3.0 #"Allegro"
-  g c
+  \tempo \markup { "Low tempo" }
+  c4 d e f g1
+  \tempoPadded #4.0 #"High tempo"
+  g4 f e d c1
 }
 @end lilypond
 
+
 Even music expressions can be passed in:
 
 @lilypond[quote,verbatim,ragged-right]