Condition Expression

condition-expression ::= 'cond' '{' condition-expression-arm (',' condition-expression-arm)* ','? '}'
condition-expression-arm ::= expression '->' expression

For each condition-expression-arm, in lexical order, evaluates the first expression (the condition). The first condition that tests as truthy causes the associated second expression (the body) to be evaluated and the evaluation of arms to stop. If no body is evaluated during this process, a panic occurs.

The whole expression results in the value of the evaluated body.