Overview:

  The mode 'play' takes its arguments (holes, notes, semitones, licks,
  scales) and plays them.  It also handles some extra keywords.

  Its arguments (which mostly can not be mixed) can be any of:

    - holes (e.g. '-1') or notes
    - notes (e.g. 'a4')
    - semitones (e.g. '+12st')
    - licks (e.g. 'st-louis')
    - scales (e.g. 'chord-i')
    - 'l', '2l', for the last lick, 2nd-to-last, etc.

  or one of the known extra arguments (that themselves might require
  additional arguments):

<%= get_extra_desc_all(for_usage: true).join("\n") %>


Usage by Examples:

  Play a few holes and notes on a harp of key c:

    harpwise play c +1 -2 c4

  Play a few semitones:

    harpwise play c +1st -4st

  Play the lick 'wade'; transpose it to d:
  
    harpwise play d wade

<%= no_lick_selecting_options %>    


  Play an earlier lick:

    harpwise play 3l

  To see a list of earlier licks:

    harpwise print licks-history


  Various ways to play all licks:

  Shuffled and in random order, without end:

    harpwise play licks

  or play them one after another as they appear in your lickfile:

    harpwise play licks --iterate cycle

  or shorter:
  
    harpwise play licks -i c

  Only play favorite licks (tag 'fav'):

    harpwise play licks --tags-all fav

  or shorter:

    harpwise play licks -t fav

  Play licks from a progression:

    harpwise play licks --lick-prog box1

  Play endless, no questions asked, but various controls available:

    harpwise play licks --lick-radio


  Play an interactive, adjustable pitch:

    harpwise play pitch

  this may help to find the key of a song that is playing: change the
  pitch by semitones, fiths or octaves until both match.

    harpwise play pitch c

  Exactly the same result as above, but with the key of c given
  explicit. This will actually start of playing g, the root note in
  second position (cross-harp).

  Note: As an alternative, you may try to hum the root note (or tonal
  center) of the song to find its key. Which is the preferred method,
  because it does not need a computer; but this command may help to
  get you started anyway.


  Play an interval:

    harpwise play inter c4 d4

  while this is beeing played you may move it around or widen or
  narrow it by semitones.

  There are multiple ways to specify an interval:
  - Either as two notes or holes
  - Or as one note or hole plus one interval (named or as semitones)

  So these are more ways to play an interval:

    harpwise play inter c4 12st    ## Note c4 and 12 Semitones

    harpwise play inter +2 pfi     ## Hole +2 and a perfect fifth

  The error message (if any) will list valid values.


  Play a note progression:

    harpwise play prog e3 7st 10st oct

  this plays the classic box pattern interactively, you may loop it or
  shift it by semitones. Holes for the harmonica (if any) are printed
  along.

  A similar progression would be:

    harpwise play prog +1 5st 7st 10st


  Building on the above, you may want to use the box pattern and the
  interactive features of 'harpwise play prog' to play (sort of) a
  full 12-bar blues: Start with the progression above, switch on loop
  and let it repeat 4 times (i.e. for 4 bars); this is the
  i-chord. Then shift by 5 Semitones up or 7 down, to get the
  iv-chord, and let this play another two times; then 5 semitones down
  to get the i-chord again, then 7 etc., etc. until all 12 bars have
  been played.

  If you want to switch between multiple progressions, separate them
  by a dot ('.') like so (using both progressions from above):

    harpwise play prog e3 7st 10st oct . +1 5st 7st 10st


  Alternatively (and without using the progression feature) you may
  get a similar result by playing predefined licks. As harpwise comes
  with licks of the 'box pattern' for chords i, iv and v, you may ask
  the wise to play the bass-line of a 12-bar blues like this:

    harpwise play box1-i box1-i box1-i box1-i box1-iv
      box1-iv box1-i box1-i box1-v box1-iv box1-i simple-turn

  which also uses the simple-turn lick at the end; you may also
  replace 'box1' with 'box2' for a variant.


    harpwise play boogie-i boogie-i boogie-iv boogie-v boogie-iv boogie-i simple-turn

  which might be a starting point for improvisation.


  Another way of playing would be:

    harpwise play chord +1 +2 +3 -3/

  plays the given holes (notes may be given too) simultanously; the
  given example is (by the way) a flat-seventh-chord, what you may
  find out by using print:

    harpwise print +1 +2 +3 -3/


  If you record yourself during lick-practice,

    harpwise play user

  plays what you have recorded before in mode 'licks' (where you need to
  trigger the recording explicitly).

