What language mechanisms does Lilypond have for si

In lilypond, I often find myself writing things like this

\version "2.14.2"
{
  r2 c2 | gis'8 gis gis gis gis gis gis gis |
}

or this

\version "2.14.2"
{
  \time 3/4 \clef bass \relative es,
  {
    <es \parenthesize es'>8\staccato g bes
    <es, \parenthesize es'>8\staccato g c
  }
}

where I repeatedly double some note one octave higher, parenthesized.

I have scoured the Lilypond documentation, but have not found easy mechanisms to avoid this duplication. A more complex way is apparently to write a music function, but that seems to require stepping out into Scheme.

The only mechanism I have found to date is one for which I don't understand the mechanism:

\version "2.14.2"
S = #staccato
P = #parenthesize
{
  \time 3/4 \clef bass \relative es,
  {
    <es \P es'>8\S g bes <es, \P es'>8\S g c
  }
}

So: How can I write my own slightly more complex abbreviations in Lilypond, without escaping to Scheme?

Update. I edited back part of my question, to indicate that (1) I'm currently using 2.14.2, which is current on Ubuntu 12.04 LTS; (2) in my second example, after the bes I want to go back to the previous es, not one octave higher: and since I'm always working in \relative mode I intentionally wrote es,; (3) I'm looking for a way to abbreviate things like 'this note with the same one an octave higher, parenthesised'.

So it seems you have two questions here. For the first one, simply use the command \repeat unfold N { ...music... }, which is described in the documentation on this link. So your code above would become something like:

\version "2.17.28"
{
  c2 \repeat unfold 8 {gis'8} r2
  es1 | \repeat unfold 2{<es \parenthesize es'>8\staccato g bes4}
}

In case of chords, there is the special command q which repeats the last chord (it only repeat the pitches and it carries no information about duration, articulation, dynamics, etc):

\version "2.17.28"
{
  <a' c'' e''>4\p-> q q q |
  q-> q\ff q\p->\< q\! |
  d'8 e' q q q2 
}

You can also define shorter parts of the code and use them in the main code, such as:

\version "2.17.28"
A = {gis'8}
B = {<es \parenthesize es'>8\staccato g bes4}

{
  c2 \repeat unfold 8 {\A} r2 |
  es1 | \repeat unfold 2 {\B} | 
  \repeat unfold 16 {\A} |
  \repeat unfold 4 {\B}
}

As for your second question, I am also starting to learn to use functions on LilyPond. But well, it seems your code is equivalent to this code here, which is the most basic function (as far as I knew) in LilyPond:

\version "2.17.28"
S = #(define-event-function (parser location) ()
  #{ \staccato #}
)

P = #(define-event-function (parser location) ()
  #{ \parenthesize #}
)

{
es1 | <es \P es'>8\S g bes <es, \P es'>\S g bes 
}

So if you just want to substitute some long text into your code, you can use this template: functionname = #(define-event-function (parser location) () #{ text #}), where functionname and text have to be changed, but the rest should remain the same. Applied, it looks like this:

\version "2.17.28"
test = #(define-event-function (parser location) ()
  #{ ^"test"\fermata\trill->\pp #}
)
{c''1\test | d'' }

For something still a bit more complex, look at this example which is a music-function using notes as argument. Note how you can then manipulate where the arguments will be in the final output:

\version "2.17.28"
func = 
#(define-music-function
  (parser location notes)
  (ly:music?)
  #{ 
    % generates 2 low pitches with cross notehead
    \override Staff.NoteHead.style = #'cross
    g,8 a,

    % reverts back to the normal noteheads and uses the notes in the argument of the function
    \revert Staff.NoteHead.style
    $notes   % these will be substituted by the arguments when you call this function on your main code

    % generates 4 low pitches with cross notehead
    \override Staff.NoteHead.style = #'cross
    g,8 a, b, c
    % reverts back to the normal noteheads for the rest of the code
    \revert Staff.NoteHead.style
  #}
)

{
  \func { c''4 } | d''1
}

Now if you want to do something more complex, then you will need to really study the documentation regarding music functions and try a lot by yourself. You can also check this and this links out.