Topic: Defining object in function call


Author: clamage@Eng.Sun.COM (Steve Clamage)
Date: 1996/01/16
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ray@cse.ucsc.edu (Ray Swartz) writes:

>I read somewhere (this newsgroup, I think) that the limitation on
>defining variables/objects in function calls had been lifted.

>I tried to find this in the April WP but failed.

If you mean something like

 void foo(int);

 main()
 {
     foo(int i = 12);  // valid?

that has never been allowed as a function call. (The example is
a valid construct, but it re-declares 'foo' to have a default
argument of value 12. It is not a function call.)
This example shows one reason why it isn't allowed: ambiguity.

A function call contains a list of expressions, and an expression
cannot contain a variable definition. (The "condition" part of a
selection statement or loop may now contain a variable definition,
but those are not expressions.)

--
Steve Clamage, stephen.clamage@eng.sun.com
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