版本：
$ moon version
moon 0.1.0 (a13731f 2023-10-08)
moonc 66309f47a /home/foo/.moon/bin/moonc
问题:
$ moon check
failed: moonc check /home/foo/tmp/hashtable/lib/rhtable/rhtable.mbt -o /home/foo/tmp/hashtable/target/check/lib/rhtable/rhtable.mi -pkg RHtable/lib/rhtable -pkg-sources RHtable/lib/rhtable:/home/foo/tmp/hashtable/lib/rhtable
......
/home/foo/tmp/hashtable/lib/rhtable/rhtable.mbt:42:20-42:31 Integer literal 0x8000_0000 is out of range.
有字面量范围检查固然不错，可是0x8000_0000应该是int32的最小值，并没有越界吧…
代码中使用此字面量的地方
func abs(self:Int) -> Int {
let min_of_i32 = 0x8000_0000
assert(self != min_of_i32, "abs() : 参数不应该为i32类型最小值")
if(self < 0){
0 - self
} else {
self
}
}
0x8000_0000 实际上已经超出了 Int 的范围，具体可以参考下面这段Rust代码的报错提示 Rust Playground
fn main (){
let a: i32 = 0x8000_0000;
let _ = a;
}
Compiling playground v0.0.1 (/playground)
error: literal out of range for `i32`
--> src/main.rs:2:16
|
2 | let a: i32 = 0x8000_0000;
| ^^^^^^^^^^^
|
= note: the literal `0x8000_0000` (decimal `2147483648`) does not fit into the type `i32` and will become `-2147483648i32`
= help: consider using the type `u32` instead
= note: `#[deny(overflowing_literals)]` on by default
help: to use as a negative number (decimal `-2147483648`), consider using the type `u32` for the literal and cast it to `i32`
|
2 | let a: i32 = 0x8000_0000u32 as i32;
| ~~~~~~~~~~~~~~~~~~~~~
error: could not compile `playground` (bin "playground") due to previous error
1 个赞
C时代的坏习惯.jpg【至少在javascript里面虽然位运算都把数字处理成(u)int32，用十六进制写0x80000000也是正整数，代表的是double范围内的最接近的。
没写负号却表示了负数，这合理么【
更新：
考虑到短期内MoonBit的内置类型不会添加无符号整数，现在把这个检查去掉了 
，不然使用起来比较麻烦
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啊，什么当场倒车【
真心的，别吧……-0x80000000又不是什么冒天下之大不韪的禁忌……
