Disallow modifications of strings #9750
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Sorry the diff is a bit messy, but it was mostly just un-indenting a lot of code which was unnecessarily indented. I can separate the two changes out for review if desired. |
|
In a discussion we decided that these operations should simply be disallowed. |
|
I couldn't really find a better spot than the effect checker to put this validation, but it's pretty easy to move around. |
This disallows `str[0] = foo` along with `foo = &mut str[i]` to prevent strings from being modified at runtime (except possibly through the `str` module) Closes rust-lang#8891
bors
added a commit
that referenced
this pull request
Oct 9, 2013
This behavior was decided to get out-right forbidden by the compiler Closes #8891
SimonSapin
added a commit
to SimonSapin/rust
that referenced
this pull request
Jul 13, 2015
... matching the existing Index impls. There is no reason not to if String implement DerefMut. The code removed in `src/librustc/middle/effect.rs` was added in rust-lang#9750 to prevent things like `s[0] = 0x80` where `s: String`, but I belive became unnecessary when the Index(Mut) traits were introduced.
flip1995
pushed a commit
to flip1995/rust
that referenced
this pull request
Dec 1, 2022
Fix [`unnecessary_lazy_eval`] when type has significant drop fix for rust-lang/rust-clippy#9427 (comment) However current implementation gives too many false positive, rending the lint almost useless. I don't know what's the best way to check if a type has a "significant" drop (in the common meaning, not the internal rustc one, for example Option<(u8, u8)> should not be considered significant) changelog: Fix [`unnecessary_lazy_eval`] when type has significant drop
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This behavior was decided to get out-right forbidden by the compiler
Closes #8891