NET/MASTER Network Control Language (NCL) Reference Manual

BOOLEXPR
Built-in Functions
106126 Tandem Computers Incorporated 4–19
EVAL
specifies that the Boolean expression is to be validated and then, if it is
syntactically correct, to be evaluated. If the expression is invalid, the result after
validation is INVALID. If the expression is valid, the result after evaluation is 1
(true), 0 (false), or BAD. See “Considerations” for a detailed description of these
values.
NOEVAL
specifies that the Boolean expression is to be validated, but that evaluation is to be
suppressed. If the expression is invalid, the result after validation is INVALID;
otherwise the result is VALID. See “Considerations” for a detailed description of
these values.
FOLD
causes lowercase alphabetic characters to be converted to uppercase alphabetic
characters. The NOFOLD modifier can override this parameter for individual
tests in the expression.
NOFOLD
causes alphabetic characters to retain their case. The FOLD modifier can override
this parameter for individual tests in the expression.
Considerations
When the EVAL parameter is specified, the built-in function returns one of the
values listed in the following table:
Result Description
INVALID The Boolean expression is invalid. The &SYSMSG variable contains a description
of the error.
BAD The Boolean expression is valid, but a variable referred to in the expression
contains data that is not valid for the specified operator. This error can occur when
a numeric value is required but a nonnumeric or null value is found, or when a
variable is expected to contain a list of valid type names but does not do so. The
&SYSMSG variable contains a description of the error.
0 The Boolean expression is valid and evaluates to false.
1 The Boolean expression is valid and evaluates to true.
When the NOEVAL operand is specified, the built-in function returns one of the
values listed in the following table:
Result Description
VALID The Boolean expression is valid; the NOEVAL operand has suppressed evaluation.
INVALID The Boolean expression is invalid. The &SYSMSG variable contains a description
of the error.