Pointer variables

Description

Pointer variables are used to store values of pointer types. These values, either identify a variable created by using the built-in procedure new on a pointer variable, or are the built-in value nil which is guaranteed not to identify any variable created using new.

Variables created by using the built-in procedure new on pointer variables are called identified variables, and are described in more detail in the next section.

Identified Variables

Identified variables are created by calling the built-in procedure new and passing a pointer variable as a parameter. Identified variables are destroyed by calling the built-in procedure dispose and passing, as a parameter, the same pointer variables that were used to create them. You should destroy identified variables after you have finished using them.

Syntax

The syntax for accessing an identified variable is given below:

(NOTE: for clarity some parts of the syntax are omitted, see Irie Pascal Grammar for the full syntax):

   identified-variable = pointer-variable '^' | pointer-variable '@'

   pointer-variable = variable-access

where pointer-variable is a reference to a pointer variable.