ArrayAccess::offsetSet Assign a value to the specified offset &reftitle.description; public voidArrayAccess::offsetSet mixedoffset mixedvalue Assigns a value to the specified offset. &reftitle.parameters; offset The offset to assign the value to. value The value to set. &reftitle.returnvalues; &return.void; &reftitle.notes; The offset parameter will be set to &null; if another value is not available, like in the following example. ]]> &example.outputs; first value [1] => second value ) ]]> This function is not called in assignments by reference and otherwise indirect changes to array dimensions overloaded with ArrayAccess (indirect in the sense they are made not by changing the dimension directly, but by changing a sub-dimension or sub-property or assigning the array dimension by reference to another variable). Instead, ArrayAccess::offsetGet is called. The operation will only be successful if that method returns by reference.