Enum IncompatibleStandards 

pub enum IncompatibleStandards {
    Allow,
    Fallback,
}

The [resolver] incompatible-standards preference knob.

The value vocabulary is deliberately identical to Cargo’s resolver.incompatible-rust-versions (allow / fallback), and the semantics mirror it: standards are a version-selection preference, never a hard constraint on solvability. See docs/design/standard-compatibility/preference-mode.md.

Variants

Allow

Standards have no influence on version selection - selection is a pure function of semver constraints, and lockfiles never move when standards change. Incompatibilities surface only through the post-resolution validation. The strict/deterministic mode.

Fallback

Prefer standard-compatible versions, falling back to newest-first when no compatible candidate exists (never a resolution failure Allow would not also produce). The default.

Implementations

impl IncompatibleStandards

pub const ALL: [Self; 2]

Both values, for enumeration in tests and diagnostics.

pub fn as_str(self) -> &'static str

The canonical spelling used in config, env vars, and messages.

pub fn parse(value: &str) -> Result<Self, UnknownIncompatibleStandards>

Parse a config / env-var value. The accepted spellings are Cargo’s verbatim.

Errors

Returns UnknownIncompatibleStandards for any other value.

Trait Implementations

impl Clone for IncompatibleStandards

fn clone(&self) -> IncompatibleStandards

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for IncompatibleStandards

impl Debug for IncompatibleStandards

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

Formats the value using the given formatter.

impl Default for IncompatibleStandards

fn default() -> IncompatibleStandards

Returns the “default value” for a type.

impl Display for IncompatibleStandards

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

Formats the value using the given formatter.

impl Eq for IncompatibleStandards

impl Hash for IncompatibleStandards

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for IncompatibleStandards

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for IncompatibleStandards