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// This test had to do with an outdated version of the iterable iface.
// However, the condition it was testing seemed complex enough to
// warrant still having a test, so I inlined the old definitions.
iface iterable<A> {
fn iter(blk: fn(A));
}
impl<A> of iterable<A> for fn@(fn(A)) {
fn iter(blk: fn(A)) { self(blk); }
}
impl of iterable<uint> for fn@(fn(uint)) {
fn iter(blk: fn(&&uint)) { self( |i| blk(i) ) }
}
fn filter<A,IA:iterable<A>>(self: IA, prd: fn@(A) -> bool, blk: fn(A)) {
do self.iter |a| {
if prd(a) { blk(a) }
}
}
fn foldl<A,B,IA:iterable<A>>(self: IA, +b0: B, blk: fn(B, A) -> B) -> B {
let mut b <- b0;
do self.iter |a| {
b <- blk(b, a);
}
ret b;
}
fn range(lo: uint, hi: uint, it: fn(uint)) {
let mut i = lo;
while i < hi {
it(i);
i += 1u;
}
}
fn main() {
let range = |a| range(0u, 1000u, a);
let filt = |a| filter(
range,
|&&n: uint| n % 3u != 0u && n % 5u != 0u,
a);
let sum = foldl(filt, 0u, |accum, &&n: uint| accum + n );
io::println(#fmt("%u", sum));
}
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