Temporarily disable all purity for debug prints

[Steven Schveighoffer]

On Tue, 12 Apr 2011 13:18:30 -0400, Walter Bright  
<newshound2 at digitalmars.com> wrote:

> On 4/12/2011 8:03 AM, Steven Schveighoffer wrote:
>> use C linkage, you can do whatever you want. It's how druntime  
>> accomplishes a
>> lot of stuff.
>>
>> For example:
>>
>> puredebug.d:
>>
>> import std.stdio;
>>
>> extern(C) void pureprint(string[] values...)
>> {
>> write("[pure debug] ");
>> foreach(value; values)
>> write(value);
>> writeln();
>> }
>>
>> puredebug.di:
>>
>> extern(C) void pureprint(string[] values...) pure;
>>
>> Should work.
>
> Yes. But it occurs to me to take the subject title literally - allow  
> impure code inside debug statements, as in:
>
> pure void foo()
> {
>      debug writeln("in foo()");
> }
>
> Simple and effective.

That works too.  I was giving an alternative that should work in the  
current compiler :)

Also, please allow debug(XYZ) writeln("in foo()");

-Steve