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InternError

Enum InternError 

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#[non_exhaustive]
pub enum InternError { SymbolSpaceExhausted, }
Expand description

An error returned when a string cannot be interned.

Interning a new string consumes one symbol from a finite space. When that space is exhausted there is no symbol left to assign, and try_intern reports it with this error rather than panicking or aliasing the string onto an existing symbol.

This enum is #[non_exhaustive]: future releases may add variants for new failure modes without it being a breaking change, so a match on it must include a wildcard arm.

§Examples

use intern_lang::{InternError, Interner};

let mut interner = Interner::new();
// Far below the symbol-space bound, interning always succeeds.
assert!(interner.try_intern("name").is_ok());

fn describe(err: InternError) -> &'static str {
    match err {
        InternError::SymbolSpaceExhausted => "out of symbols",
        _ => "unknown interning error",
    }
}
assert_eq!(describe(InternError::SymbolSpaceExhausted), "out of symbols");

Variants (Non-exhaustive)§

This enum is marked as non-exhaustive
Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.
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SymbolSpaceExhausted

The symbol space is exhausted: the interner has already issued all u32::MAX symbols, so no new string can be assigned one.

Reaching this requires interning over four billion distinct strings, which exhausts memory on any normal machine long before the symbol space. A caller that must handle the boundary explicitly — rather than relying on it being unreachable — should use try_intern and treat this variant as a hard stop: the interner cannot accept further distinct strings.

Trait Implementations§

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impl Clone for InternError

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fn clone(&self) -> InternError

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
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impl Copy for InternError

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impl Debug for InternError

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

Formats the value using the given formatter. Read more
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impl Display for InternError

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

Formats the value using the given formatter. Read more
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impl Eq for InternError

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impl Error for InternError

1.30.0 · Source§

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any. Read more
1.0.0 · Source§

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

1.0.0 · Source§

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

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fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)
Provides type-based access to context intended for error reports. Read more
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impl Hash for InternError

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

Feeds this value into the given Hasher. Read more
1.3.0 · Source§

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

Feeds a slice of this type into the given Hasher. Read more
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impl PartialEq for InternError

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

Tests for self and other values to be equal, and is used by ==.
1.0.0 (const: unstable) · Source§

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

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

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T> ToString for T
where T: Display + ?Sized,

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fn to_string(&self) -> String

Converts the given value to a String. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.