On 3/19/2011 2:25 PM, Michel Fortin wrote:
On 2011-03-19 14:14:51 -0400, Michel Fortin <michel.for...@michelf.com> said:I'm not too convinced about the "I know what I'm doing" argument when I look at this example from asyncBuf's documentation: auto lines = File("foo.txt").byLine(); auto duped = map!"a.idup"(lines); // Necessary b/c byLine() recycles buffer // Fetch more lines in the background while we process the lines already // read into memory into a matrix of doubles. double[][] matrix; auto asyncReader = taskPool.asyncBuf(duped); foreach(line; asyncReader) { auto ls = line.split("\t"); matrix ~= to!(double[])(ls); } Look at the last line of the foreach. You are appending to a non-shared array from many different threads. How is that not a race condition?.... or maybe I just totally misunderstood asyncBuf. Rereading the documentation I'm under the impression I'd have to write this to get what I expected: foreach (line; parallel(asyncReader)) ... And that would cause a race condition. If that's the case, the example is fine. Sorry for the misunderstanding.
Right. And this is pretty obviously a race. The other example (without the parallel) is completely safe.
