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#[doc = "Operations and constants for `int`"];
#[cfg(target_arch="x86")]
const min_value: int = -1 << 31;
#[cfg(target_arch="x86_64")]
const min_value: int = -1 << 63;
// FIXME: Find another way to access the machine word size in a const expr
// (See Issue #2001)
#[cfg(target_arch="x86")]
const max_value: int = (-1 << 31)-1;
#[cfg(target_arch="x86_64")]
const max_value: int = (-1 << 63)-1;
pure fn min(x: int, y: int) -> int { if x < y { x } else { y } }
pure fn max(x: int, y: int) -> int { if x > y { x } else { y } }
pure fn add(x: int, y: int) -> int { ret x + y; }
pure fn sub(x: int, y: int) -> int { ret x - y; }
pure fn mul(x: int, y: int) -> int { ret x * y; }
pure fn div(x: int, y: int) -> int { ret x / y; }
pure fn rem(x: int, y: int) -> int { ret x % y; }
pure fn lt(x: int, y: int) -> bool { ret x < y; }
pure fn le(x: int, y: int) -> bool { ret x <= y; }
pure fn eq(x: int, y: int) -> bool { ret x == y; }
pure fn ne(x: int, y: int) -> bool { ret x != y; }
pure fn ge(x: int, y: int) -> bool { ret x >= y; }
pure fn gt(x: int, y: int) -> bool { ret x > y; }
pure fn positive(x: int) -> bool { ret x > 0; }
pure fn negative(x: int) -> bool { ret x < 0; }
pure fn nonpositive(x: int) -> bool { ret x <= 0; }
pure fn nonnegative(x: int) -> bool { ret x >= 0; }
#[doc = "Produce a uint suitable for use in a hash table"]
pure fn hash(x: int) -> uint { ret x as uint; }
#[doc = "Iterate over the range `[lo..hi)`"]
fn range(lo: int, hi: int, it: fn(int)) {
let mut i = lo;
while i < hi { it(i); i += 1; }
}
#[doc = "
Parse a buffer of bytes
# Arguments
* buf - A byte buffer
* radix - The base of the number
"]
fn parse_buf(buf: [u8], radix: uint) -> option<int> {
if vec::len(buf) == 0u { ret none; }
let mut i = vec::len(buf) - 1u;
let mut start = 0u;
let mut power = 1;
if buf[0] == ('-' as u8) {
power = -1;
start = 1u;
}
let mut n = 0;
loop {
alt char::to_digit(buf[i] as char, radix) {
some(d) { n += (d as int) * power; }
none { ret none; }
}
power *= radix as int;
if i <= start { ret some(n); }
i -= 1u;
};
}
#[doc = "Parse a string to an int"]
fn from_str(s: str) -> option<int> { parse_buf(str::bytes(s), 10u) }
#[doc = "Convert to a string in a given base"]
fn to_str(n: int, radix: uint) -> str {
assert (0u < radix && radix <= 16u);
ret if n < 0 {
"-" + uint::to_str(-n as uint, radix)
} else { uint::to_str(n as uint, radix) };
}
#[doc = "Convert to a string"]
fn str(i: int) -> str { ret to_str(i, 10u); }
#[doc = "Returns `base` raised to the power of `exponent`"]
fn pow(base: int, exponent: uint) -> int {
if exponent == 0u { ret 1; } //Not mathemtically true if [base == 0]
if base == 0 { ret 0; }
let mut my_pow = exponent;
let mut acc = 1;
let mut multiplier = base;
while(my_pow > 0u) {
if my_pow % 2u == 1u {
acc *= multiplier;
}
my_pow /= 2u;
multiplier *= multiplier;
}
ret acc;
}
#[doc = "Computes the bitwise complement"]
pure fn compl(i: int) -> int {
uint::compl(i as uint) as int
}
#[doc = "Computes the absolute value"]
fn abs(i: int) -> int {
if negative(i) { -i } else { i }
}
#[test]
fn test_from_str() {
assert from_str("0") == some(0);
assert from_str("3") == some(3);
assert from_str("10") == some(10);
assert from_str("123456789") == some(123456789);
assert from_str("00100") == some(100);
assert from_str("-1") == some(-1);
assert from_str("-3") == some(-3);
assert from_str("-10") == some(-10);
assert from_str("-123456789") == some(-123456789);
assert from_str("-00100") == some(-100);
assert from_str(" ") == none;
assert from_str("x") == none;
}
#[test]
fn test_parse_buf() {
import str::bytes;
assert parse_buf(bytes("123"), 10u) == some(123);
assert parse_buf(bytes("1001"), 2u) == some(9);
assert parse_buf(bytes("123"), 8u) == some(83);
assert parse_buf(bytes("123"), 16u) == some(291);
assert parse_buf(bytes("ffff"), 16u) == some(65535);
assert parse_buf(bytes("FFFF"), 16u) == some(65535);
assert parse_buf(bytes("z"), 36u) == some(35);
assert parse_buf(bytes("Z"), 36u) == some(35);
assert parse_buf(bytes("-123"), 10u) == some(-123);
assert parse_buf(bytes("-1001"), 2u) == some(-9);
assert parse_buf(bytes("-123"), 8u) == some(-83);
assert parse_buf(bytes("-123"), 16u) == some(-291);
assert parse_buf(bytes("-ffff"), 16u) == some(-65535);
assert parse_buf(bytes("-FFFF"), 16u) == some(-65535);
assert parse_buf(bytes("-z"), 36u) == some(-35);
assert parse_buf(bytes("-Z"), 36u) == some(-35);
assert parse_buf(str::bytes("Z"), 35u) == none;
assert parse_buf(str::bytes("-9"), 2u) == none;
}
#[test]
fn test_to_str() {
import str::eq;
assert (eq(to_str(0, 10u), "0"));
assert (eq(to_str(1, 10u), "1"));
assert (eq(to_str(-1, 10u), "-1"));
assert (eq(to_str(255, 16u), "ff"));
assert (eq(to_str(100, 10u), "100"));
}
#[test]
fn test_pow() {
assert (pow(0, 0u) == 1);
assert (pow(0, 1u) == 0);
assert (pow(0, 2u) == 0);
assert (pow(-1, 0u) == 1);
assert (pow(1, 0u) == 1);
assert (pow(-3, 2u) == 9);
assert (pow(-3, 3u) == -27);
assert (pow(4, 9u) == 262144);
}
#[test]
fn test_overflows() {
assert (max_value > 0);
assert (min_value <= 0);
assert (min_value + max_value + 1 == 0);
}
// Local Variables:
// mode: rust;
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End:
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