code: function (source, pattern) {
      var results = [], match;
      while ((match = pattern.exec(source)) !== null)
        results.push(match[1]);
      return results;
    }
docs: If all lines are indented, we should trim them all to the same point so that code doesn't need to start at column 0 in the source (see GitHub Issue #105) Helper to extract captures from the regex