var letterRE = new RegExp('[a-zA-Z]', 'g'),
    digitRE = RegExp('[0-9]');

// from jQuery

var rformElems = /^(?:input|select|textarea)$/i,
	rkeyEvent = /^key/,
	rmouseEvent = /^(?:mouse|contextmenu)|click/,
	rfocusMorph = /^(?:focusinfocus|focusoutblur)$/,
	rtypenamespace = /^([^.]*)(?:\.(.+)|)$/;

// from Lo-Dash

var reEscapedHtml = /&(?:amp|lt|gt|quot|#39);/g;
var reEmptyStringLeading = /\b__p \+= '';/g,
    reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
    reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;