Arrastres: function scheme question - Built from ideas of Simon and David -- Dynamic mark at the end of a bar

[Stephen MacNeil]

I used the first snippet posted by Simon for an Arrastres function. Then I noticed Davids post for afterGrace so I tried my hand at that.

Both work but I have a few questions.

In the first posted by simon I did it my typical way. And it works like all my other functions. Typically I use modified lily functions like bendAfter (one of my favorite to use). In all cases I can't figure out how to add the command in the function. So although it works it could be better.

Here is the code

 %%%%%%%%%%%%%%%

\version "2.18.2"

Arrastres =

#(define-music-function

(parser location len

mus note)

(number?

ly:music? ly:music?)

#{

\afterGrace

$mus

{

\once \override Flag.stroke-style = #"grace"

\once \override NoteHead.extra-spacing-width = #`(,len . 1)

s1*0 \stemUp $note

}

#})

mus = \relative c' {

\time 2/4

\key g \major

\stemDown dis16 fis dis b c a g \Arrastres #-3 fis \glissando c'8|

<a c>2

}

\score {

\mus

}

%%%%%%%%%%%%%%%%%%

My question is where do I add \glissando in the function so I don't have to write it everytime.

The second modified from the snippet posted by David afterGrace works great and I even got it so i don't need \glissando. But again I have questions.

Here is the code

%%%%%%%%%%%%%

\version "2.18.2"

Fraction = #(cons 6 8)

Arrastres =

#(define-music-function (parser location len main grace) (number? ly:music? ly:music?)

(_i "Create @var{grace} note(s) after a @var{main} music _expression_.")

(let ((main-length (ly:music-length main))

(fraction (ly:parser-lookup parser 'Fraction)))

(make-simultaneous-music

(list

main

(make-sequential-music

(list

(make-music 'SkipMusic

'duration (ly:make-duration

0 len

(* (ly:moment-main-numerator main-length)

(car fraction))

(* (ly:moment-main-denominator main-length)

(cdr fraction))))

#{

\once \override Flag.stroke-style = #"grace"

#}

(make-music

'GraceMusic

'element grace)))

#{

\glissando

#}))))

\relative c' {c \Arrastres #6 c e8 e}

%%%%%%%%%%%%%%%%%%%%%%%

well where to begin...

first why is Fraction = #(cons 6 8) and not Fraction = #(cons 1 1) or 2 2 etc. 6 8 seams rather small. Is it so in some cases there is not to much space?

second

'duration (ly:make-duration

0 len

was set 0 0 ... again why. I assume the first number is notes occupied? and the second distance. Why 0 on the second. and isn't this just a recap of Fraction = #(cons 6 8)? or is one gliss length and the other note distance (both having the same effect -- so make one 0 )-- i assume.

Thanks

Stephen