scheme-tutorial.itely: avoid unnecessary copying

scheme-tutorial.itely: avoid unnecessary copying

[Carl, 2011-10-28 20:51:38]

LGTM

Carl

[Ian Hulin (gmail), 2011-10-28 23:04:31]

David,
I think you've updated an example in two places, and added material which needs
to reference the second example after the first one. You're trying to describe
things about coding within music functions before the text gets round to
mentioning them.  This section is trying to hand-hold the reader through the
stages of implementing a marcato music function as it stands your extra info
about avoiding the destructive update the event-chord is just too early.
Cheers,
Ian

http://codereview.appspot.com/5314065/diff/1/Documentation/extending/scheme-t...
File Documentation/extending/scheme-tutorial.itely (right):

http://codereview.appspot.com/5314065/diff/1/Documentation/extending/scheme-t...
Documentation/extending/scheme-tutorial.itely:1241: name is @code{add-marcato},
and has one variable called
name is @code {add-marcato}, and has one parameter called

http://codereview.appspot.com/5314065/diff/1/Documentation/extending/scheme-t...
Documentation/extending/scheme-tutorial.itely:1242: @code{event-chord}.  In
Scheme, the type of variable is often clear
@code{event-chord}.  In Scheme, the usage of a parameter or variable is often
clear

http://codereview.appspot.com/5314065/diff/1/Documentation/extending/scheme-t...
Documentation/extending/scheme-tutorial.itely:1256: @code{ly:music-deep-copy} to
create a complete copy of the music.
modifying the original.

If this is a problem, we need to use @code{ly:music-deep-copy} to create a
complete copy of the music, @emph{and} to code this within a music function.

http://codereview.appspot.com/5314065/diff/1/Documentation/extending/scheme-t...
Documentation/extending/scheme-tutorial.itely:1263: mechanisms for dealing with
music.
Hmmm... Good information, but you're proposing something different from
what's in the new  @example in 1233-1237.  You probably should finish off
describing things in this example and talk about music function possibilities
lower down when the document introduces define-music-function.  Are you talking
about passing Lilypond input parameters to Scheme code in a music function?  If
so give it its own @example further down in the text after line 1302 somewhere. 
This section of text is leading the reader through a step-by-step example, and
this excellent info needs to be fitted in at the right place.

[dak, 2011-10-28 23:49:48]

On 2011/10/28 23:04:31, Ian Hulin (gmail) wrote:
> David,
> I think you've updated an example in two places, and added material which
needs
> to reference the second example after the first one.

I disagree.  I see only one example here.  The intermediate definition
of a Scheme function is just a temporary simplification: the function
is never used or demonstrated.  There is also no information how one
would actually get the information for passing into the Scheme
function at the Scheme level.

Since no attempt to do a complete example in Scheme is made, it would
be nonsensical to add complications only required for a full Scheme
version, only to drop them again later before even using them.

Since I don't have the time and energy to do this in the desired way
(I was just trying to correct an example in discord with reality,
making people think that about half of music-function-init.ly is
defective), I am marking this as Patch_abandoned and Frog, and maybe
somebody else can be interested in working on it until it meets the
required standards.