Enum rustc_mir::borrow_check::LocalMutationIsAllowed

enum LocalMutationIsAllowed {
    Yes,
    ExceptUpvars,
    No,
}

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

When checking permissions for a place access, this flag is used to indicate that an immutable local place can be mutated.

FIXME: @nikomatsakis suggested that this flag could be removed with the following modifications:

• Merge check_access_permissions() and check_if_reassignment_to_immutable_state()
• Split is_mutable() into is_assignable() (can be directly assigned) and is_declared_mutable()
• Take flow state into consideration in is_assignable() for local variables

Variants

Yes

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

ExceptUpvars

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

We want use of immutable upvars to cause a "write to immutable upvar" error, not an "reassignment" error.

No

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

Trait Implementations

impl Copy for LocalMutationIsAllowed

impl Clone for LocalMutationIsAllowed

fn clone(&self) -> LocalMutationIsAllowed

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl PartialEq for LocalMutationIsAllowed

fn eq(&self, other: &LocalMutationIsAllowed) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl Eq for LocalMutationIsAllowed

fn assert_receiver_is_total_eq(&self)

impl Debug for LocalMutationIsAllowed

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.