Enum ErrorKind 

#[non_exhaustive]
pub enum ErrorKind {
    EmptyGroup,
    EmptyGroupBranch,
    EmptyExpression,
    TopLevelAction,
    MissingAction,
    MissingDelimiter(char),
    MultipleBranches,
    UnexpectedChar(char),
    UnexpectedEof,
    UnknownArgumentTag(char),
    UnknownTag(char),
}

A list specifying the different categories of errors that can be encountered while parsing a structural regular expression.

It is used with the ParseError type.

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.

EmptyGroup

A parallel group was provided without any branches.

EmptyGroupBranch

A branch in a parallel group contained no expressions.

EmptyExpression

The provided expression was empty.

TopLevelAction

The provided top level expression was a single action. Such an expression would only ever run the action once for all inputs.

MissingAction

Comilation options require an action for all matches but none was specified.

MissingDelimiter(char)

An expected delimiter was not found.

Typically this is encountered when an parallel group or delimited string is missing its closing delimiter.

MultipleBranches

Multiple distinct expressions were present in the provided input.

To run multiple expressions over a haystack you should provide a top level parallel group.

UnexpectedChar(char)

An unexpected character was encountered in the input expression.

UnexpectedEof

End of file was encountered before a full expression could be parsed.

UnknownArgumentTag(char)

An action tag was found that did not match the allowed single argument tags specified as part of a StructexBuilder.

UnknownTag(char)

An action tag was found that did not match the allowed zero argument tags specified as part of a StructexBuilder.

Trait Implementations

impl Clone for ErrorKind

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 ErrorKind

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

Formats the value using the given formatter.

impl Display for ErrorKind

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

Formats the value using the given formatter.

impl Eq for ErrorKind

impl PartialEq for ErrorKind

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ErrorKind