Struct Issue 

#[non_exhaustive]
pub struct Issue {
    pub kind: IssueKind,
    pub value: String,
    pub suggestion: Option<String>,
}

Why a value failed to validate.

Structured rather than pre-rendered, for the same reason crate::Presentation carries semantic hints rather than colours: the embedder owns presentation. A frontend can localize the text, or offer Issue::suggestion as a one-tap correction instead of prose. Display renders the English default.

#[non_exhaustive]: an issue can gain context (a span, a source) without costing downstream a major. Build one with Issue::unknown, Issue::retired or Issue::custom; reading the fields is unchanged.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

kind: IssueKind

What went wrong.

value: String

The offending value, as text.

suggestion: Option<String>

A near miss from the vocabulary, when one is close enough to be worth offering.

Implementations

impl Issue

pub fn unknown(value: impl Into<String>) -> Self

A value that is not in the vocabulary.

pub fn retired(value: impl Into<String>) -> Self

A value that is in the vocabulary but retired.

pub fn custom(value: impl Into<String>, message: impl Into<String>) -> Self

An embedder-defined issue with its own message.

pub fn with_suggestion(self, suggestion: impl Into<String>) -> Self

Attach a near-miss suggestion.

Trait Implementations

impl Clone for Issue

fn clone(&self) -> Issue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Issue

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

Formats the value using the given formatter.

impl Display for Issue

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

Formats the value using the given formatter.

impl Eq for Issue

impl PartialEq for Issue

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Issue