Ellery Newcomer wrote:
what is the purpose of the expression grammar
Expression:
AssignExpression
AssignExpression , Expression
?
(emphasis on the comma)
To allow two expressions separated by a comma to be another expression. This is
only useful if the expression before the last comma has side-effects of course,
since its value isn't used. Such an expression returns the result of its
right-hand side.
For example: (foo(), bar()) is an expression that calls foo(), then calls bar()
and evaluates to the return value of bar().
This is mostly used in the increment clause of a for loop, like this:
for (int i = 0; i < max; i++, someOtherCounter++)
