whole_func_string: function() {
          // TODO: work out when to clear this out for the plain Requisition case
          // this._hints = [];
          this.getAssignments(true).forEach(function(assignment) {
              this._hints.push(assignment.getHint());
          }, this);
          Hint.sort(this._hints);
  
          // We would like to put some initial help here, but for anyone but
          // a complete novice a 'type help' message is very annoying, so we
          // need to find a way to only display this message once, or for
          // until the user click a 'close' button or similar
          // TODO: Add special case for '' input
      }
func_code_string: function() {
          // TODO: work out when to clear this out for the plain Requisition case
          // this._hints = [];
          this.getAssignments(true).forEach(function(assignment) {
              this._hints.push(assignment.getHint());
          }, this);
          Hint.sort(this._hints);
  
          // We would like to put some initial help here, but for anyone but
          // a complete novice a 'type help' message is very annoying, so we
          // need to find a way to only display this message once, or for
          // until the user click a 'close' button or similar
          // TODO: Add special case for '' input
      }
func_documentation_string: Collect the statuses from the Assignments.
  The hints returned are sorted by severity