guitar tabs, brackets

[Thomas Volpini]

Hello Everyone,

i've stumbled upon a strange problem:

this works:

{
  \new TabStaff  <<
  {
%   \set TabStaff.stringTunings = #'(-1 -1 -1 -1 -1 -1)
    \set TabStaff.minimumFret = #12
    c''  g'
  }
  >>
}



but this:

{
  \new TabStaff  <<
  {
    \set TabStaff.stringTunings = #'(-1 -1 -1 -1 -1 -1)
    \set TabStaff.minimumFret = #12
    c''  g'
  }
  >>
}

causes an error:


Interpreting music... ERROR: In procedure list-ref:
ERROR: Argument 2 out of range: 6


furthermore, could someone explain the difference between <<, {, and whatever
other brackets there may be to me (and possibly include the explanation in the
documentation)?

thanks
Thomas