Enum CheckError 

#[non_exhaustive]
pub enum CheckError {
    DuplicateDefinition {
        name: String,
        span: Span,
    },
    IncrementalWithoutBase {
        name: String,
        shadows_core: bool,
        span: Span,
    },
    UndefinedRule {
        name: String,
        span: Span,
    },
    InvalidRepeatRange {
        min: u64,
        max: u64,
        span: Span,
    },
    InvalidNumericRange {
        lo: u64,
        hi: u64,
        span: Span,
    },
    LeftRecursion {
        cycle: Vec<String>,
    },
}

A structural problem: the grammar cannot be used at all.

Variants (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.

DuplicateDefinition

A rule was defined twice with =.

Fields

name: String

The rule name.

span: Span

Where the second definition is.

IncrementalWithoutBase

name =/ … with no prior name = ….

Fields

name: String

The rule name.

shadows_core: bool

Whether the name is one of the implicit core rules (D34).

span: Span

Where the incremental definition is.

UndefinedRule

A rule reference names no user rule and no core rule.

Fields

name: String

The referenced name.

span: Span

Where the reference is.

InvalidRepeatRange

A repetition whose lower bound exceeds its upper bound (D18).

Fields

min: u64

Lower bound.

max: u64

Upper bound.

span: Span

Where the repetition is.

InvalidNumericRange

A numeric range whose lower endpoint exceeds its upper endpoint (D18).

Fields

lo: u64

Lower endpoint.

hi: u64

Upper endpoint.

span: Span

Where the range is.

LeftRecursion

A cycle in the first-graph: the recognizer could not terminate on it.

Global, not per start rule — an unreachable left-recursive rule still fails check. Left recursion is always a grammar bug for an ABNF recognizer, unlike prose values and unrepresentable terminals, which are legitimate ABNF this crate does not support (SCOPE.md 6.4).

Fields

cycle: Vec<String>

The cycle, in definition order.

Implementations

impl CheckError

pub fn span(&self) -> Option<Span>

Where in the source this error is, if it has a single location.

LeftRecursion has none: a cycle is a property of several rules at once, and pointing at any one of them would be arbitrary.

pub fn render(&self, src: &str) -> String

Renders the error against the grammar text it came from.

Trait Implementations

impl Clone for CheckError

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CheckError

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

Formats the value using the given formatter.

impl Display for CheckError

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

Formats the value using the given formatter.

impl Eq for CheckError

impl Error for CheckError

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

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

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

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

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.

impl PartialEq for CheckError

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for CheckError