error when using JavaScript framework angularjs

[MuhsinZeptoa]

I used this code in my view file:
@{{myForm.myInput.$valid}}

But I got the following error:

A PHP Error was encountered
Severity: Notice

Message: Undefined variable: valid

Filename: libraries/Slice.php(519) : eval()'d code

Line Number: 3

Backtrace:

File: D:\xampp\htdocs\test\application\libraries\Slice.php(519) : eval()'d code
Line: 3
Function: _error_handler

File: D:\xampp\htdocs\test\application\libraries\Slice.php
Line: 519
Function: eval

File: D:\xampp\htdocs\test\application\libraries\Slice.php
Line: 364
Function: _run

File: D:\xampp\htdocs\test\application\controllers\Method.php
Line: 20
Function: view

File: D:\xampp\htdocs\test\index.php
Line: 315
Function: require_once