> p $class<br>
ChildClass<br>
> x %ChildClass<br>
empty array<br>
> x %ChildClass::ChildClass<br>
0  'Invalid_characters'<br>
1  '[^\\W-]'<br>
2  'Column_header'<br>
3  '^(cell|name)$'<br>
4  'Blank_ok'<br>
5  'no'<br>
6  'Input_column'<br>
7  'Unknown'<br>
8  'Field_length'<br>
9  20