User-defined data parts provide prototypes for variables or for
other, more specific parts. A data part occupies no storage. EGL reserves
storage only when you declare a variable based on the part.
EGL offers the following data parts:
- DataItem
- A simple user-defined data type that associates a name, a primitive
type, and optional properties.
- Record
- A complex user defined data type that associates a name with a
set of variable definitions plus optional properties. The properties
can associate the type with an external data store such as a record
from a file or a row in a relational database table.
- Exception
- A type of record containing information about system or program
errors. The system provides a number of basic exceptions; you can
define others yourself.
Each of these parts has a unique set of properties that you can
set to control the behavior of the program that you generate from
the EGL source.