David Brown <david.brown@hesbynett.no> writes:Agreed (I also agree on the correction of terminology).
[...]In C, an expression statement "expr;" causes the expression to be[...]
evaluated as a void expression for its side effects (§6.8.4p2). You
can, arguably, say that C also requires all statements to be of "void"
type, just like Pascal - but the cast-to-void is done implicitly to
treat "expr;" as "(void) expr;".
In an expression statement, the expression is "evaluated as a void
expression for its side effects". I think that's equivalent to
convert (not casting!) it to void, but the standard doesn't describe
it that way.
6.3.2.2: "If an expression of any other type [other than void]Correct.
is evaluated as a void expression, its value or designator is
discarded."
But statements have no type.
I did not mean to suggest that statements in C actually have a type, and that their type is "void". It was a philosophical wandering - I was not trying to stay true to the grammar and terminology of either the C or Pascal language standards.
What I meant was that if you were to think that statements /did/ have type void, the resulting language would be basically the same. It gives a way to think about C and Pascal that shows that though they appear to have a different model of statements and expressions, they are fundamentally similar - the distinction being that C has an explicit conversion to void when non-void expressions are used in a statement context.
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