Using javascript regex to parse strings starting with "$" and other conditions -

this difficult regex wrap head around. i'd words start $. conditions are:

• string must start $ , preceding character must either beginning of string or space.

• if $ followed ", in between "" must captured. both quotes must present or nothing captured.

• "" used capturing more 1 word

• $ not match anything

some examples:

• bob gave jane $4

  ["4"] captured

• $"10 thousand dollars" lot more $1 , $-3

  ["10 thousand dollars", "1", "-3"] captured

• bob paid $590 $micro$oft $and" wa$ reimbursed $nine

  ["590", "micro$oft", "nine"] captured

• alice says $"hello $world!"

  ["hello $world!"] captured

• $ yup$

  nothing captured

i tried playing around horrible. look-aheads make tricky.

function parse(text) {      var re = /(\s|^)\$(?:"([^"]*)"|([^\s"]+)(?!\s))/g;      re.lastindex = 0;      var result = [];      var match;      while (match = re.exec(text)) {          result.push(match[2] || match[3]);      }      return result;  }    var tests = [    'bob gave jane $4',    '$"10 thousand dollars" lot more $1 , $-3',    'bob paid $590 $micro$oft $and" wa$ reimbursed $nine',    'alice says $"hello $world!"',    '$ yup$'  ];    $('<table>').append([    $('<thead>').append([      $('<tr>').append([        $('<th>').text('test'),        $('<th>').text('captures')      ])    ]),    $('<tbody>').append(      $.map(tests, function (test) {        var result = parse(test);        return $('<tr>').append([          $('<td>').append([            $('<code>').text(test)          ]),          $('<td>').append([            $('<code>').text(json.stringify(result))          ])        ]);      })    )  ]).appendto('#output23');

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>  <div id="output23"></div>