ember-runtime.js
function(keyName, increment) {
    if (!increment) { increment = 1; }
    set(this, keyName, (get(this, keyName) || 0)+increment);
    return get(this, keyName);
  }
function(keyName, increment) {
    if (!increment) { increment = 1; }
    set(this, keyName, (get(this, keyName) || 0)+increment);
    return get(this, keyName);
  }
function ( keyName , increment ) { if ( ! increment ) { increment = 1 ; } set ( this , keyName , ( get ( this , keyName ) || 0 ) + increment ) ; return get ( this , keyName ) ; }
Set the value of a property to the current value plus some amount.

```javascript
person.incrementProperty('age');
team.incrementProperty('score', 2);
```

@method incrementProperty
@param {String} keyName The name of the property to increment
@param {Object} increment The amount to increment by. Defaults to 1
@return {Object} The new property value
Set the value of a property to the current value plus some amount .