Bug 4441 – TDPL Example on P401 & 402 doesn't compile on D2.047, 2.046, 2.045, 2.044. Seems to be a problem involves tuples and []

The example: import std.concurrency, std.stdio, std.contracts; /*std.contracts was missing in the book, but this is fairly trivial change*/ void main() { auto low = 0, high = 100; auto tid = spawn(&writer); foreach(i; low .. high) { writeln("Main thread: ",i); tid.send(thisTid,i); enforce(receiveOnly!Tid() == tid); } } void writer() { for(;;) { auto msg = receiveOnly!(Tid,int)(); writeln("Secondary thread: ", msg[1]); //Line 17 msg[0].send(thisTid); //Line 18 } } thread_test.d(17): Error: no [] operator overload for type Tuple!(Tid,int) thread_test.d(18): Error: no [] operator overload for type Tuple!(Tid,int) Trying to compile with version 2.044-2.046 produces these errors thread_test.d(10): Error: template std.typecons.Tuple!(Tid).Tuple.opEquals(T) if (is(typeof(T.field))) does not match any function template declaration thread_test.d(10): Error: template std.typecons.Tuple!(Tid).Tuple.opEquals(T) if (is(typeof(T.field))) cannot deduce template function from argument types !()(Tid)

Possible minimal case: import std.typecons; void main() { Tuple!(int,int) x; int y=x[0]; } thread_test.d(5): Error: no [] operator overload for type Tuple!(int,int)

This is one big reason for the introduction of alias this. However, there was never time to fix it. I agree it's a major bug.

Fixed DMD2.050.