Re: CC-mode highlight change between 24.5 and 25

[Davis Herring]

> I feared as much.  I've often wondered why the C++ language developers
> have had such a low regard for unambiguous syntax, such as most other
> (computer) languages have.  I've cursed them for it on more than one
> occasion.

Blame Ritchie (if we may speak ill of the dead), for similar vagueness 
dates to C:

/* Choose one: */
/* typedef int foo; */
/* void foo(int); */

int arg;

void f() {foo(arg);}

Depending on which of the declarations you include, "foo(arg)" is a 
declaration of a local variable "arg" or is a call to the function foo. 
(Obviously the declarations would typically be hidden in a header.)

Part of the reason for the introduction of uniform initialization in 
C++11 is to avoid the most-vexing-parse (though it does nothing for the 
above).

> In other words, only semantics determine that the line 4 is a variable
> declaration rather than a function declaration.  CC Mode doesn't do
> semantics, except to a _very_ limited degree.  So we're reduced, yet
> again, to difficult and unreliable heuristics.  Curse the C++ language
> developers!

At least here the heuristic of "out of a function, it's a function; 
inside a function, it's a variable" works pretty well and both ways 
(since most people avoid global variables with constructors).

Davis

PS - If you like, I'll be sure to mention your curse in Issaquah 
(https://isocpp.org/std/meetings-and-participation/upcoming-meetings). 
(Just be sure to tell me on how many occasions you have cursed WG21; 
curses queue like POSIX real-time signals.)

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