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# Error: error:nonassign
Non-Assignable Expression

    Expression '{0}' is non-assignable. Element: {1}

## Description

This error occurs when expression the ngModel directive is bound to is a non-assignable expression.

Examples using assignable expressions include:

    <input ng-model="namedVariable">
    <input ng-model="myObj.someProperty">
    <input ng-model="indexedArray[0]">

Examples of non-assignable expressions include:

    <input ng-model="foo + bar">
    <input ng-model="42">
    <input ng-model="'oops'">
    <input ng-model="myFunc()">

Always make sure that the expression bound via `ngModel` directive can be assigned to.

For more information, see the ngModel API doc.