// the # of rows we want to add to the top and bottom of the rendered grid rows 
var EXCESS_ROWS = 6;
var SCROLL_THRESHOLD = 4;
var ASC = "asc";
// constant for sorting direction
var DESC = "desc";
// constant for sorting direction
var NG_FIELD = '_ng_field_';
var NG_DEPTH = '_ng_depth_';
var NG_HIDDEN = '_ng_hidden_';
var NG_COLUMN = '_ng_column_';
var CUSTOM_FILTERS = /CUSTOM_FILTERS/g;
var COL_FIELD = /COL_FIELD/g;
var DISPLAY_CELL_TEMPLATE = /DISPLAY_CELL_TEMPLATE/g;
var EDITABLE_CELL_TEMPLATE = /EDITABLE_CELL_TEMPLATE/g;
var TEMPLATE_REGEXP = /<.+>/;