Where PL/I requires
a (possibly signed) constant, a restricted expression can
be used. A restricted expression is an expression whose value is
calculated at compile time and used as a constant. For example,
you can use expressions to define constants required for:
- Extents in static, parameter, and based declarations
- Extents in entry descriptions
- Values and iteration factors to be used in static initialization
A restricted expression is identical to a normal expression but
requires that each operand be:
- A constant or a named constant. A named constant must be declared
before it is used.
- A built-in function applied to a restricted expression(s),
where the built-in function is from the following categories:
- String-handling
- Arithmetic (except RANDOM)
- Mathematical
- Floating-point inquiry
- Floating-point manipulation
- Integer manipulation
- Precision-handling
- Array-handling functions DIMENSION, LBOUND, and HBOUND
- Storage-control functions BINARYVALUE, LENGTH, NULL, OFFSETVALUE, POINTERVALUE,
SIZE, STORAGE, and SYSNULL
- Type functions BIND, CAST, FIRST, LAST, RESPEC and SIZE
|
This information center is powered by Eclipse technology. (http://www.eclipse.org)