1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::int;
use std::uint;
fn uint_range(lo: uint, hi: uint, it: &fn(uint) -> bool) -> bool {
range(lo, hi).advance(it)
}
fn int_range(lo: int, hi: int, it: &fn(int) -> bool) -> bool {
range(lo, hi).advance(it)
}
fn int_range_step(a: int, b: int, step: int, it: &fn(int) -> bool) -> bool {
int::range_step(a, b, step, it)
}
fn uint_range_step(a: uint, b: uint, s: int, it: &fn(uint) -> bool) -> bool {
uint::range_step(a, b, s, it)
}
pub fn main() {
println("num-range start");
// int and uint have same result for
// Sum{2 <= i < 100} == (Sum{1 <= i <= 99} - 1) == n*(n+1)/2 - 1 for n=99
let mut sum = 0u;
do uint_range(2, 100) |i| {
sum += i;
true
};
assert_eq!(sum, 4949);
let mut sum = 0i;
do int_range(2, 100) |i| {
sum += i;
true
};
assert_eq!(sum, 4949);
// elements are visited in correct order
let primes = [2,3,5,7];
let mut prod = 1i;
do uint_range(0, 4) |i| {
prod *= int::pow(primes[i], i);
true
};
assert_eq!(prod, 1*3*5*5*7*7*7);
let mut prod = 1i;
do int_range(0, 4) |i| {
prod *= int::pow(primes[i], i as uint);
true
};
assert_eq!(prod, 1*3*5*5*7*7*7);
// empty ranges
do int_range(10, 10) |_| {
fail!("range should be empty when start == stop");
true
};
do uint_range(10, 10) |_| {
fail!("range should be empty when start == stop");
true
};
// range iterations do not wrap/overflow
let mut oflo_loop_visited = ~[];
do uint_range_step(uint::max_value-15, uint::max_value, 4) |x| {
oflo_loop_visited.push(uint::max_value - x);
true
};
assert_eq!(oflo_loop_visited, ~[15, 11, 7, 3]);
let mut oflo_loop_visited = ~[];
do int_range_step(int::max_value-15, int::max_value, 4) |x| {
oflo_loop_visited.push(int::max_value - x);
true
};
assert_eq!(oflo_loop_visited, ~[15, 11, 7, 3]);
// range_step never passes nor visits the stop element
do int_range_step(0, 21, 3) |x| {
assert!(x < 21);
true
};
// range_step_inclusive will never pass stop element, and may skip it.
let mut saw21 = false;
do uint::range_step_inclusive(0, 21, 4) |x| {
assert!(x <= 21);
if x == 21 { saw21 = true; }
true
};
assert!(!saw21);
let mut saw21 = false;
do int::range_step_inclusive(0, 21, 4) |x| {
assert!(x <= 21);
if x == 21 { saw21 = true; }
true
};
assert!(!saw21);
// range_step_inclusive will never pass stop element, but may visit it.
let mut saw21 = false;
do uint::range_step_inclusive(0, 21, 3) |x| {
assert!(x <= 21);
printfln!("saw: %u", x);
if x == 21 { saw21 = true; }
true
};
assert!(saw21);
let mut saw21 = false;
do int::range_step_inclusive(0, 21, 3) |x| {
assert!(x <= 21);
if x == 21 { saw21 = true; }
true
};
assert!(saw21);
}
|
