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Conditions

$$ Condition ::= Comparison ({"and" Comparison} | {"or" Comparison}) .
$$ Comparison ::= ["not"] (Expression [Comparison-Operator Expression]
                  | Match-Comparison) .
$$ Comparison-Operator ::= "=" | "/=" | "~" | "/~" | "in" | "less" | "greater"
                           | "less_equal" | "greater_equal" .

A condition can either be true or false, as in ``Verb = Verb'' or `` Verb = Noun'', respectively. An expression that is evaluated to any of the symbols yes or no is a valid condition.

A condition can be used everywhere a (non-constant) value is needed. It will evaluate to yes or no. In this case, the condition must be surrounded by parentheses.



Subsections

Bjoern Beutel