src/main/java/com/bazaarvoice/jless/parser/Parser.java
Rule Parameter() {
        return Sequence(
                Variable(), push(new VariableDefinitionNode(match())), peek().setVisible(!isParserTranslationEnabled()), Ws0(),
                ':', Ws0(),
                ExpressionPhrase(), peek(1).addChild(new ExpressionGroupNode(pop()))
        );
    }
Rule Parameter() {
        return Sequence(
                Variable(), push(new VariableDefinitionNode(match())), peek().setVisible(!isParserTranslationEnabled()), Ws0(),
                ':', Ws0(),
                ExpressionPhrase(), peek(1).addChild(new ExpressionGroupNode(pop()))
        );
    }
Rule Parameter ( ) { return Sequence ( Variable ( ) , push ( new VariableDefinitionNode ( match ( ) ) ) , peek ( ) . setVisible ( ! isParserTranslationEnabled ( ) ) , Ws0 ( ) , ' ' , Ws0 ( ) , ExpressionPhrase ( ) , peek ( 1 ) . addChild ( new ExpressionGroupNode ( pop ( ) ) ) ) ; }
Variable Ws0 ':' Ws0 ExpressionPhrase
Variable Ws0 : Ws0 ExpressionPhrase