• Steve Teale <steve.teale britseyeview.com> Jun 04 2009
• bearophile <bearophileHUGS lycos.com> Jun 04 2009
• BCS <ao pathlink.com> Jun 04 2009
• Daniel Keep <daniel.keep.lists gmail.com> Jun 04 2009
• Steve Teale <steve.teale britseyeview.com> Jun 04 2009
• Daniel Keep <daniel.keep.lists gmail.com> Jun 04 2009
• Steve Teale <steve.teale britseyeview.com> Jun 05 2009

Steve Teale <steve.teale britseyeview.com> writes:

If I write:

static if (cond1)
{
 ...
}
else static if (cond2)
{
 ...
}
else
{
 ...
}

is the block after the final else 'static'? Would it be better if the 'static'
before the whole sequence of tests applied throughout rather than having to be
explicitly restated in some places, but not in others?

Steve

bearophile <bearophileHUGS lycos.com> writes:

Steve Teale:

is the block after the final else 'static'?<


Yes, it is.


Would it be better if the 'static' before the whole sequence of tests applied
throughout rather than having to be explicitly restated in some places, but not
in others?<


Few times I have forgotten to put a "static" in such chain of static ifs (so I
may appreciate a kind of static switch) but in practice I think your idea will
lead to other bugs. So it may be better to not change the current design.

Bye,
bearophile

BCS <ao pathlink.com> writes:

Reply to Steve,

 If I write:
 
 static if (cond1)
 {
 ...
 }
 else static if (cond2)
 {
 ...
 }
 else
 {
 ...
 }
 is the block after the final else 'static'? Would it be better if the
 'static' before the whole sequence of tests applied throughout rather
 than having to be explicitly restated in some places, but not in
 others?
 
 Steve
 


Whatever is used, both of these (and other variations) should be cleanly 
and consistently representable.

static if(foo) {     static if(bar) {} else {}   }
else {    static if(baz) {} else {}   }

static if(foo) {     if(bar) {} else {}   } 
else {     if(baz) {} else {}   }

Daniel Keep <daniel.keep.lists gmail.com> writes:

Steve Teale wrote:
 If I write:
 
 static if (cond1)
 {
  ...
 }
 else static if (cond2)
 {
  ...
 }
 else
 {
  ...
 }
 
 is the block after the final else 'static'? Would it be better if the 'static'
before the whole sequence of tests applied throughout rather than having to be
explicitly restated in some places, but not in others?
 
 Steve


I don't think so.  The problem is that there's no such thing as "chained
ifs" in the language.  What you're actually looking at is this:

static if (cond1)
{
 ...
}
else
{
 static if (cond2)
 {
  ...
 }
 else
 {
  ...
 }
}

Once you realise that there's nothing special about either "else if" or
"else static if", it makes perfect sense.

Steve Teale <steve.teale britseyeview.com> writes:

Daniel Keep Wrote:

 
 
 Steve Teale wrote:
 If I write:
 
 static if (cond1)
 {
  ...
 }
 else static if (cond2)
 {
  ...
 }
 else
 {
  ...
 }
 
 is the block after the final else 'static'? Would it be better if the 'static'
before the whole sequence of tests applied throughout rather than having to be
explicitly restated in some places, but not in others?
 
 Steve


 I don't think so.  The problem is that there's no such thing as "chained
 ifs" in the language.  What you're actually looking at is this:
 
 static if (cond1)
 {
  ...
 }
 else
 {
  static if (cond2)
  {
   ...
  }
  else
  {
   ...
  }
 }
 
 Once you realise that there's nothing special about either "else if" or
 "else static if", it makes perfect sense.


Daniel,

So I have to write

static if (cond1)
{
}
else static if (cond2)
{
}
else static if (true)
{
   // for the default alternative?
}

Looks a bit strange
Steve

Daniel Keep <daniel.keep.lists gmail.com> writes:

Steve Teale wrote:
 ...
 
 Daniel,
 
 So I have to write
 
 static if (cond1)
 {
 }
 else static if (cond2)
 {
 }
 else static if (true)
 {
    // for the default alternative?
 }


No.

 Looks a bit strange
 Steve


That's because it's wrong.

static if (cond) ... else ... is a single structure.  The branch is
chosen at compile-time.  It doesn't make sense for the else to somehow
not be part of the static if.

Steve Teale <steve.teale britseyeview.com> writes:

Daniel Keep Wrote:


 That's because it's wrong.
 
 static if (cond) ... else ... is a single structure.  The branch is
 chosen at compile-time.  It doesn't make sense for the else to somehow
 not be part of the static if.


Daniel,

Sorry, I'm there now.

I agree completely that otherwise it does not make sense, but what you say now
was not the impression I got from the previous answers.

I had unfortunately, been looking for the appropriate documentation in all the
wrong places. A search in the html files comes up with version.html,
which did not seem to be that relevant. Perhaps the file name should reflect
the html title, and be conditional-compilation.html.

Thanks Steve