Re: Using map instead of iteration

[spir]

On 03/06/2011 02:43 PM, Russel Winder wrote:
I have a code fragment:
   auto threads = new Thread[numberOfThreads] ;
   foreach ( i ; 0 .. numberOfThreads ) {
     void delegate ( ) closedPartialSum ( ) {
       immutable id = i ;
       return ( ) { partialSum ( id , sliceSize , delta ) ; } ;
     }
     threads[i] = new Thread ( closedPartialSum ) ;
   }

which clearly should be doable using map from std.algorithm.  So I
tried:

   auto threads = map ! ( function Thread ( int i ) {
       void delegate ( ) closedPartialSum ( ) {
         immutable id = i ;
         return ( ) { partialSum ( id , sliceSize , delta ) ; } ;
       }
       return new Thread ( closedPartialSum ) ;
     } ) ( 0 .. numberOfThreads )

which fails:

pi_d2_threadsGlobalState.d(41): found '..' when expecting ','
pi_d2_threadsGlobalState.d(57): semicolon expected following auto
declaration, not 'foreach'

So clearly 0 .. numberOfThreads only means a range of integers in a
foreach or array index only and not everywhere as it does in all
sensible languages :-((

I am clearly missing something, anyone any ideas?

Without trying to study the code's detainls: "( 0 .. numberOfThreads )" has 
very few chances to be accepted by the parser ;-)
Note: there is no interval literal in D. Instead uses of i..j in slicing and 
foreach both are pure syntactic honey.

Denis
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