How to use

topoSort

function

in

Array

/*  ------------------------------------------------------------------------ */

_.withTest (['Array', 'topomerge'], function () {

   $assert ( [['all','your',                'to','us'],
         [      'your',       'belong',     'us'],
         [             'base','belong','to'     ],
         [      'your','base'                   ]].topoMerge (),
        /* -------------------------------------- */
         ['all','your','base','belong','to','us'])

/*  ------------------------------------------------------------------------ */

}, function () {

  $mixin (Array, {

    topoMerge () {                                               var edges    = []
      for (var i = 0, ni = this.length;         i < ni; i++) { var sequence = this[i]
      for (var j = 0, nj = sequence.length - 1; j < nj; j++) {
        edges.push ([
          sequence[j    ],
          sequence[j + 1]]) } }

      return edges.topoSort ()
    }
  })
})