XGC CORAL 66: Language Reference Manual
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6.2. Conditional Expressions

A conditional expression has the form

Conditionalexpression ::=
     IF Condition
     THEN Expression
     ELSE Expression

with the usual interpretation.

6.2.1. Conditions

A condition is made up of arithmetic comparisons connected by Boolean operators OR and AND, of which AND is the more tightly binding. The permitted arithmetic comparisons are less than, less than or equal to, equal to, greater than or equal to, greater than, and not equal to. The syntax rules are

Condition ::=
Condition OR Subcondition
Subcondition

Subcondition ::=
Subcondition AND Comparison
Comparison

Comparison ::=
Simpleexpression Comparator Simpleexpression

Comparator ::=
    <
    <=
    =
    >=
    >
    <>

The Boolean operators have their usual meanings, the OR being inclusive. Conditions are evaluated from left to right only as far as is necessary to determine their truth or falsity.