static/ext/src/lang/Date.js
function(character) {
        var f = utilDate.formatCodes[character];

        if (f) {
          f = typeof f == 'function'? f() : f;
          utilDate.formatCodes[character] = f; // reassign function result to prevent repeated execution
        }

        // note: unknown characters are treated as literals
        return f || ("'" + Ext.String.escape(character) + "'");
    }
function(character) {
        var f = utilDate.formatCodes[character];

        if (f) {
          f = typeof f == 'function'? f() : f;
          utilDate.formatCodes[character] = f; // reassign function result to prevent repeated execution
        }

        // note: unknown characters are treated as literals
        return f || ("'" + Ext.String.escape(character) + "'");
    }
private