why does aura attribute initialize collection variables without default?

Question

I need to perform different behavior based on whether a String array flow attributes has been set or not. And need to differentiate between an empty array and between null value, however it seems lightning initializes these attributes! Anyone know how to default these values to null?

Unexpectedly initialized to empty string:

<aura:attribute name="listNoDefault" type="List" access="public"/>
<aura:attribute name="listNullDefault" type="List" access="public" default="null"/>
<aura:attribute name="stringArrayNoDefault" type="String[]" access="public"/>
<aura:attribute name="stringArrayNullDefault" type="String[]" access="public" default="null"/>    

Not initialized default is null!

<aura:attribute name="objectNoDefault" type="Object" access="public"/>

Answer 1

Maybe you can try assigning default values to these attributes during onInit method handler