• Burton Radons (9/9) Sep 19 2004 This code causes the compiler to crash:
• Lars Ivar Igesund (10/21) Sep 19 2004 I think this leads to an incorrect program, as version (none) becomes
• Stewart Gordon (22/39) Sep 28 2004
• Walter (2/2) Sep 19 2004 It's fixed now. It turns into:
• Stewart Gordon (3/5) Sep 27 2004 You mean you've changed it so that that's valid D syntax?
• Walter (4/10) Sep 30 2004 No. I meant:

Burton Radons <burton-radons shaw.ca> writes:

This code causes the compiler to crash:

     void foo ()
     {
         if (x)
             version (none)
                 foo;
     }

The specification doesn't say what a collapsed version/debug statement 
turns into, so I don't know how it's supposed to behave.

Lars Ivar Igesund <larsivar igesund.net> writes:

Burton Radons wrote:

 This code causes the compiler to crash:
 
     void foo ()
     {
         if (x)
             version (none)
                 foo;
     }
 
 The specification doesn't say what a collapsed version/debug statement 
 turns into, so I don't know how it's supposed to behave.

I think this leads to an incorrect program, as version (none) becomes 
nothing:

void foo ()
{
   if (x)
}

which is wrong because there is no statement following if (x). The 
compiler shouldn't crash, though.

Lars Ivar Igesund

Stewart Gordon <Stewart_member pathlink.com> writes:

In article <cikkvs$1f9n$1 digitaldaemon.com>, Lars Ivar Igesund 
says...

 Burton Radons wrote:
 
 This code causes the compiler to crash:
 
     void foo ()
     {
         if (x)
             version (none)
                 foo;
     }


<snip>
 void foo ()
 {
 if (x)
 }
 
 which is wrong because there is no statement following if (x).  The 
 compiler shouldn't crash, though.

The D versioning system isn't a text preprocessor.  As such, it is 
pointless to try and think of version blocks as reducing to textual 
nothingness.

Rather, it reduces to semantic nothingness, an effective 'nop' 
statement.

Another way to think of it is by imagining that there are braces:

void foo() {
if (x) {
version (none) {
foo;
}
}
}

The statement forms

if ( Expression ) Statement

if ( Expression ) { Statement }

are identical in effect,  By converting to the latter, it is easy to 
see the result of version reduction.

Stewart.

"Walter" <newshound digitalmars.com> writes:

It's fixed now. It turns into:

    if (x) ;

Stewart Gordon <Stewart_member pathlink.com> writes:

In article <cil2q3$1l6i$1 digitaldaemon.com>, Walter says...
It's fixed now. It turns into:

    if (x) ;

You mean you've changed it so that that's valid D syntax?

Stewart.

"Walter" <newshound digitalmars.com> writes:

"Stewart Gordon" <Stewart_member pathlink.com> wrote in message
news:cj9ltc$16k1$1 digitaldaemon.com...
 In article <cil2q3$1l6i$1 digitaldaemon.com>, Walter says...
It's fixed now. It turns into:

    if (x) ;

 You mean you've changed it so that that's valid D syntax?

No. I meant:

    if (x) { }