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Subrule Invokations

$$ Subrule-Invocation ::= Rule-Name "(" Expression {"," Expression} ")" .
$$ Rule-Name ::= Identifier .

A subrule is invoked when an expression ``subrule (value1, value2, $...$)'' is evaluated. The expression yields the value that is returned by the return statement in the subrule. The number of parameters in a subrule invokation must match the number of parameters in the subrule definition.

There is a number of default subrules which are predefined. They are called functions and they all take one parameter only.



Bjoern Beutel