** Overview of 'harpwise quiz'

  The mode 'quiz' is a quiz on music theory, ear and memory. It is meant
  as a fun way to increase your musical abilities. Quiz comes in different
  flavours (see below). It issues questions and asks for answers.

  All flavours offer various sorts of help, allowing to view and explore
  the question at hand from a different angle.

  If you invoke mode 'quiz' with the argument 'random' (or 'ran'), a
  flavour is chosen at random. To try another flavour, just restart
  harpwise, e.g. by pressing ctrl-z.  For a chosen flavour, different
  questions of this flavour are asked in an endless loop.
  
  There are <%= $extras_joined_to_desc[:quiz].length %> flavours of quiz
  listed below; however, you do not need to memorize them, as they will be
  explained on the spot when they appear.

  For an overview, here are the available flavours:

<%= get_extra_desc_all(mode: :quiz, for_usage: true).join("\n") %>
  
** Usage by Examples

  The wise chooses a quiz-flavour at random (key of c):

    #+begin_src 
    harpwise quiz c random
    #+end_src

  this is the preferred way to get used to this mode.

  To switch to a different, random mode, issue signal ctrl-z.


  Some examples that choose a quiz flavour or a collection of flavours
  explicitly:
  

  Wise plays 5 notes from the scale major_pentatonic for a
  chromatic harmonica of key a and then asks you to play them
  back (then repeat):

    #+begin_src 
    harpwise quiz chromatic a blues replay 5
    #+end_src

  In the examples above, the type of harmonica (e.g. richter or
  chromatic), the key (e.g. c or a) or the number of holes may be
  omitted and are then taken from the config or defaults; so

    #+begin_src 
    harpwise q major replay
    #+end_src

  is valid as well (but would choose a richter harp).


  This example chooses the a flavour-collection:

    #+begin_src 
    harpwise quiz no-mic
    #+end_src

  the collection 'no-mic' includes a number of different flavours, which
  have in common, that they do not need your microphone and do not require
  you to play your harp. This can be helpful e.g. when quizzing in public
  transport.


  Wise plays a scale and asks you for its name:

    #+begin_src 
    harpwise quiz hear-scale
    #+end_src

** Quick Start

    #+begin_src 
    harpwise quiz ran
    #+end_src


  And at any time, type 'ctrl-z' to try another flavour.
  
