# Annotation Glossary

### A

allow-none

  NULL is OK, both for passing and for returning.

### E

element-type

  Generics and defining elements of containers and arrays.

### I

in

  Parameter for input. Default is transfer none.

### O

out

  Parameter for returning results. Default is transfer full.

### T

transfer full

  The caller owns the data, and is responsible for free it.

transfer none

  The data is owned by the callee, which is responsible of freeing it.