=head2 Comparing Parameterized types to Structured types
Parameterized constraints are built into core Moose and you are probably already
-familar with the type constraints 'HashRef' and 'ArrayRef'. Structured types
+familiar with the type constraints 'HashRef' and 'ArrayRef'. Structured types
have similar functionality, so their syntax is likewise similar. For example,
you could define a parameterized constraint like: