starvingmap.rs

//#[no_uv]; //Works as expected w/ no_uv

extern mod std;

use std::{rand, task, vec};
use std::rand::Rng;
use std::hashmap::HashMap;
use std::task::TaskBuilder;


pub fn named_task(name: ~str) -> TaskBuilder {
    let mut ui_task = task::task();
    ui_task.name(name);
    ui_task
}

fn spawnWithMap(i: int) {
    do named_task(format!("inner{}", i)).spawn {
        // Vectors don't have a problem.
        // let v: ~[int] = vec::with_capacity(100000);
        // println!("Vec{} created!", i);

        // HashMaps do.
        let m: HashMap<~str, ~str> = HashMap::new();
        println!("HashMap{} created!", i);

        // Looks like the HashMap problem stems from the random numbers.
        //let mut r = rand::task_rng();
        //let r1: int = r.gen();
        //let r2: int = r.gen();
        //println!("Random{} created!", i);
    }
}

fn tightloop() {
    let mut i = 0;
    while i<1000000000 {
        i += 1;
    }
    println!("Finished tightloop!");
}


fn main() {
    //With the outer task, at least one of the spawnWithMap calls
    //will not print "HashMapX created!" until after tightloop, regardless
    //of how long I make tightloop run.  But if I comment out the
    //outer task, they seem to all finish okay.

    //Creating Vecs seems fine.  I'm thinking the issue with HashMaps is
    //due to the rng stuff it uses.  Validated this by just getting some
    //random numbers, which seems to have the same problem.
    do named_task(~"outer").spawn {
        spawnWithMap(1);
        spawnWithMap(2);
        spawnWithMap(3);

        tightloop();
    }
}