我们该如何正确实现一个 i64 和 f64 数值的比较

试试在 Rust 或者 JS 里看看 905325263262362321.0 < 905325263262362322.0 的结果

@ecnelises 我发现 JS 认为他们相等。

905325263262362321.0 < 905325263262362322.0
false
905325263262362321.0 > 905325263262362322.0
false
905325263262362321.0 == 905325263262362322.0
true

float 自己都不敢和自己比

```rust
/// x <= y
fn is_less_eq(x: i64, y: f64) -> bool {
const H: f64 = 9223372036854775808f64;

if !y.is_finite() {
return false;
} else if y >= H {
return true;
} else if y < -H {
return false;
} else {
let y = y.floor() as i64;
x <= y
}
}

fn main() {
println!("{}", is_less_eq(9007199254740993, 9007199254740992.0));
println!("{}", is_less_eq(1, 1.125f64));
println!("{}", is_less_eq(1, 0.125f64));
println!("{}", is_less_eq(1, f64::MIN_POSITIVE));
println!("{}", is_less_eq(-1, -0.125f64));
println!("{}", is_less_eq(-1, -1.125f64));
println!("{}", is_less_eq(-1, -1f64));
println!("{}", is_less_eq(i64::MIN, i64::MIN as f64));
println!("{}", is_less_eq(i64::MIN, -9223372036854777856f64));
}
```

test

@liuxu c 也是这样。。。