// Test rules governing higher-order pure fns. pure fn range(from: uint, to: uint, f: fn(uint)) { let mut i = from; while i < to { f(i); // Note: legal to call argument, even if it is not pure. i += 1u; } } pure fn range2(from: uint, to: uint, f: fn(uint)) { do range(from, to) |i| { f(i*2u); } } pure fn range3(from: uint, to: uint, f: fn(uint)) { range(from, to, f) } pure fn range4(from: uint, to: uint) { range(from, to, print) //~ ERROR access to impure function prohibited in pure context } pure fn range5(from: uint, to: uint, x: {f: fn(uint)}) { range(from, to, x.f) //~ ERROR access to impure function prohibited in pure context } pure fn range6(from: uint, to: uint, x: @{f: fn(uint)}) { range(from, to, x.f) //~ ERROR access to impure function prohibited in pure context } pure fn range7(from: uint, to: uint) { do range(from, to) |i| { print(i); //~ ERROR access to impure function prohibited in pure context } } pure fn range8(from: uint, to: uint) { range(from, to, noop); } fn print(i: uint) { #error["i=%u", i]; } pure fn noop(_i: uint) {} fn main() { }