DMD 0.165 release

[Sean Kelly]

Walter Bright wrote:
> Sean Kelly wrote:
>> Thanks.  I suppose it's worth mentioning that lazy evaluation can 
>> result in some confusing errors similar to those encountered with 
>> macro functions vs. normal functions.  For example:
>>
>>     void fn( char delegate() ch )
>>     {
>>         if( ch() == 'c' || ch() == 'd' )
>>         {
>>             printf( "match\n" );
>>         }
>>     }
>>
>>     size_t pos = 0;
>>     char[] buf = "abdc";
>>
>>     fn( buf[++pos] );
>>
>> The above code would print "match" because pos would be incremented 
>> twice.  This makes API changes from the classic to lambda syntax a 
>> risky venture, as it risks silently breaking once-working code.
> 
> It doesn't break existing once-working code, because the example shown 
> will not compile with 0.164 and earlier compilers.

I was thinking more of converting an API call from:

     void fn( char ch );

to:

     void fn( char delegate() ch );

Both accept the same parameters under DMD 165, but the result may be 
different.  But this is something library developers simply must keep in 
mind more than a problem with the technique itself.  It would be easy 
enough to document how the supplied delegate is evaluated.


Sean