user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add explanation for #[must_use] on string replace methods

Browse source
This commit is contained in:
Manish Goregaokar 2018-05-07 09:30:11 -07:00
parent f8b774fbf1
commit a72a0801bd
1 changed files with 4 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

6
src/liballoc/str.rs
View file

@ -207,7 +207,8 @@ impl str {
/// let s = "this is old";
/// assert_eq!(s, s.replace("cookie monster", "little lamb"));
/// ```
#[must_use]
#[must_use = "this returns the replaced string as a new allocation, \
without modifying the original"]
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn replace<'a, P: Pattern<'a>>(&'a self, from: P, to: &str) -> String {
@ -247,7 +248,8 @@ impl str {
/// let s = "this is old";
/// assert_eq!(s, s.replacen("cookie monster", "little lamb", 10));
/// ```
#[must_use]
#[must_use = "this returns the replaced string as a new allocation, \
without modifying the original"]
#[stable(feature = "str_replacen", since = "1.16.0")]
pub fn replacen<'a, P: Pattern<'a>>(&'a self, pat: P, to: &str, count: usize) -> String {
// Hope to reduce the times of re-allocation