angularjs - Why a method in expression is called two times in angular.js -

i want know why method called 2 times while used in angularjs binding expression.

you can find code here @ jsbin

why callme() method called 2 times. found same question posted not satisfactory answer. , if want avoid called 2 times how it.

you binding function expression

<p>{{callme()}}</p> 

that's why it's called many times, because runs everytime when angularjs calls digest()... here picture how digest work maybe helps better...