asString 
  Returns the attribute cast to PangoAttrString.
This is mainly useful for language bindings.
Return
The attribute as PangoAttrString, or null if it's not a string attribute
Since
1.50
Returns the attribute cast to PangoAttrString.
This is mainly useful for language bindings.
The attribute as PangoAttrString, or null if it's not a string attribute
1.50