What the book means is that you cannot have both the char in there and the extra brackets (which are needed to make it make sense). You have sort of cut out the context:
* This refers to a previous example.Quote:
Although the example* also shows variables defined within while, if, and switch statements, this kind of definition is much less common than those in for expressions, possibly because the syntax is so constrained. For example, you cannot have any parentheses.