pub struct BuildError { /* private fields */ }
Expand description

An error that occurs when construction of a Regex fails.

A build error is generally a result of one of two possible failure modes. First is a parse or syntax error in the concrete syntax of a pattern. Second is that the construction of the underlying regex matcher fails, usually because it gets too big with respect to limits like Config::nfa_size_limit.

This error provides very little introspection capabilities. You can:

  • Ask for the PatternID of the pattern that caused an error, if one is available. This is available for things like syntax errors, but not for cases where build limits are exceeded.
  • Ask for the underlying syntax error, but only if the error is a syntax error.
  • Ask for a human readable message corresponding to the underlying error.
  • The BuildError::source method (from the std::error::Error trait implementation) may be used to query for an underlying error if one exists. There are no API guarantees about which error is returned.

When the std feature is enabled, this implements std::error::Error.

Implementations§

source§

impl BuildError

source

pub fn pattern(&self) -> Option<PatternID>

If it is known which pattern ID caused this build error to occur, then this method returns it.

Some errors are not associated with a particular pattern. However, any errors that occur as part of parsing a pattern are guaranteed to be associated with a pattern ID.

Example
use regex_automata::{meta::Regex, PatternID};

let err = Regex::new_many(&["a", "b", r"\p{Foo}", "c"]).unwrap_err();
assert_eq!(Some(PatternID::must(2)), err.pattern());
source

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

If this error occurred because the regex exceeded the configured size limit before being built, then this returns the configured size limit.

The limit returned is what was configured, and corresponds to the maximum amount of heap usage in bytes.

source

pub fn syntax_error(&self) -> Option<&Error>

If this error corresponds to a syntax error, then a reference to it is returned by this method.

Trait Implementations§

source§

impl Clone for BuildError

source§

fn clone(&self) -> BuildError

Returns a copy of the value. Read more
1.0.0 · source§

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

Performs copy-assignment from source. Read more
source§

impl Debug for BuildError

source§

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

Formats the value using the given formatter. Read more
source§

impl Display for BuildError

source§

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

Formats the value using the given formatter. Read more
source§

impl Error for BuildError

source§

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

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
source§

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

Auto Trait Implementations§

Blanket Implementations§

source§

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

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for T
where T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

source§

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

Mutably borrows from an owned value. Read more
source§

impl<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

source§

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

source§

fn into(self) -> U

Calls U::from(self).

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

source§

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

§

type Owned = T

The resulting type after obtaining ownership.
source§

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
source§

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
source§

impl<T> ToString for T
where T: Display + ?Sized,

source§

default fn to_string(&self) -> String

Converts the given value to a String. Read more
source§

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

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

§

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

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.