std: note that std::str::from_utf8* functions are aliases to std::<str>::from_utf8* methods

Signed-off-by: xizheyin <xizheyin@smail.nju.edu.cn>

Author: xizheyin

library/core/src/str/converts.rs

@@ -6,6 +6,7 @@ use crate::{mem, ptr};
 
 /// Converts a slice of bytes to a string slice.
 ///
+/// This is an alias to [`str::from_utf8`].
 /// A string slice ([`&str`]) is made of bytes ([`u8`]), and a byte slice
 /// ([`&[u8]`][byteslice]) is made of bytes, so this function converts between
 /// the two. Not all byte slices are valid string slices, however: [`&str`] requires
@@ -97,6 +98,8 @@ pub const fn from_utf8(v: &[u8]) -> Result<&str, Utf8Error> {
 
 /// Converts a mutable slice of bytes to a mutable string slice.
 ///
+/// This is an alias to [`str::from_utf8_mut`].
+///
 /// # Examples
 ///
 /// Basic usage:
@@ -142,6 +145,8 @@ pub const fn from_utf8_mut(v: &mut [u8]) -> Result<&mut str, Utf8Error> {
 /// Converts a slice of bytes to a string slice without checking
 /// that the string contains valid UTF-8.
 ///
+/// This is an alias to [`str::from_utf8_unchecked`].
+///
 /// See the safe version, [`from_utf8`], for more information.
 ///
 /// # Safety
@@ -178,6 +183,8 @@ pub const unsafe fn from_utf8_unchecked(v: &[u8]) -> &str {
 /// Converts a slice of bytes to a string slice without checking
 /// that the string contains valid UTF-8; mutable version.
 ///
+/// This is an alias to [`str::from_utf8_unchecked_mut`].
+///
 /// See the immutable version, [`from_utf8_unchecked()`] for documentation and safety requirements.
 ///
 /// # Examples