function isOfType(T,maybeSomething){return maybeSomething&&maybeSomething.constructor===T;}
var len=attr('length'),isString=partialComplete(isOfType,String);function defined(value){return value!==undefined;}
function hasAllProperties(fieldList,o){return(o instanceof Object)&&all(function(field){return(field in o);},fieldList);}
function cons(x,xs){return[x,xs];}