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
|
use std::cmp::{min, max};
pub fn clamp<T: Ord>(val: T, lower: T, upper: T) -> T{
max(min(val, upper), lower)
}
pub fn strip_prefix<'a>(txt: &'a str, prefix: &'a str) -> Option<&'a str> {
if txt.starts_with(prefix) {
Some(txt.split_at(prefix.len()).1)
} else {
None
}
}
use std::fs;
use std::path::Path;
use crate::{
errors::AnyError,
aerr
};
pub fn write_file_safe<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> Result<(), AnyError> {
let temppath = path
.as_ref()
.with_file_name(
format!(
"tempfile_{}_{}.tmp",
path.as_ref().file_name().ok_or(aerr!("writing to directory"))?.to_str().unwrap_or("invalid"),
rand::random::<u64>()
)
);
fs::write(&temppath, contents)?;
fs::rename(&temppath, path)?;
Ok(())
}
#[macro_export]
macro_rules! hashmap {
( $($key:expr => $value:expr ),* ) => {{
#[allow(unused_mut)]
let mut h = std::collections::HashMap::new();
$(
h.insert($key, $value);
)*
h
}}
}
#[cfg(test)]
mod tests {
use std::collections::HashMap;
#[test]
fn test_hashmap_macro() {
let mut h = hashmap!("hello" => 1, "world" => 2);
assert_eq!(h.remove("hello"), Some(1));
assert_eq!(h.remove("world"), Some(2));
assert!(h.is_empty());
let h2: HashMap<i32, usize> = hashmap!();
assert!(h2.is_empty());
assert_eq!(h2, HashMap::new());
}
}
|