An expression-statement evaluates a given expression. The value computed by the expression, if any, is discarded.
Not all expressions are permitted as statements. In particular, expressions such as x
+
y
and x
==
1
that have no side-effects, but merely compute a value (which will be discarded), are not permitted as statements.
Execution of an expression statement evaluates the contained expression and then transfers control to the end point of the expression statement.