Struct ParseError 

pub struct ParseError { /* private fields */ }

Typed parse error with structured diagnostics and a backwards compatible Display rendering.

Diagnostic detail lives behind a Box so ParseResult stays small in Result returns (cold path allocation only).

Implementations

impl ParseError

pub fn pest( message: String, expected: Vec<String>, hint: Option<String>, ctx: &SpanContext<'_>, ) -> Self

Pest grammar failure. message must already contain the parse error (expected: ...) header; the location block is appended by Display unless already present.

pub fn invalid_syntax( command: &str, message: String, found: Option<String>, expected: Vec<String>, hint: Option<String>, ctx: &SpanContext<'_>, ) -> Self

Known command or keyword with malformed arguments.

pub fn unknown_command( name: &str, message: String, hint: Option<String>, ctx: &SpanContext<'_>, ) -> Self

Truly unknown command name. Callers must ensure classify sent keyword led lines to invalid_syntax instead.

pub fn structural(rule: &str, message: String, ctx: &SpanContext<'_>) -> Self

Structural failure (guards, blocks, WITH_IO, LET, FOR, IF).

pub fn validation(command: &str, message: String, ctx: &SpanContext<'_>) -> Self

Arity, flag, or static type failure for a known command.

pub fn with_span(self, ctx: &SpanContext<'_>) -> Self

Enrich an error produced without span context (e.g. from a direct lower_command call) with the caller’s location. Existing span fields are only overwritten when the current value is None, so pest spans are never clobbered.

pub fn with_step(self, step_index: usize) -> Self

Attach a step index (builder style).

pub fn kind(&self) -> &ParseErrorKind

Machine readable kind.

pub fn line(&self) -> usize

1-based line number (0 means unknown, direct calls only).

pub fn col_start(&self) -> Option<usize>

1-based start column, when known.

pub fn col_end(&self) -> Option<usize>

1-based end column (inclusive), when known.

pub fn source_line(&self) -> Option<&str>

Raw source line text, when available.

pub fn step_index(&self) -> Option<usize>

Zero-based step index, when known.

pub fn found(&self) -> Option<&str>

What was found (command name or rendered args), when known.

pub fn expected(&self) -> &[String]

Expected syntax alternatives.

pub fn hint(&self) -> Option<&str>

Concrete hint with an example, when known.

Trait Implementations

impl Clone for ParseError

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 ParseError

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

Formats the value using the given formatter.

impl Display for ParseError

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

Formats the value using the given formatter.

impl Error for ParseError

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.