Struct vectorscan::expression::Literal

pub struct Literal(/* private fields */);

Available on crate feature compiler only.

A literal byte string.

Unlike for Expression, Database::compile_literal() will parse the string content in a literal sense without any regular grammars. For example, the expression abc? simply means a char sequence of a, b, c, and ?. The ? here doesn’t mean 0 or 1 quantifier under regular semantics.

Also unlike Expression, the underlying vectorscan library interprets literal patterns with a pointer and a length instead of a NULL-terminated string. Importantly, this allows it to contain \0 or NULL bytes itself!

Finally note that literal expressions do not support an “info” interface like Expression::info() and Expression::ext_info(), since most of those properties can be inferred from the literal string itself.

Instances can be created equivalently with Self::new() or str::parse() via the str::FromStr impl:

 use vectorscan::expression::Literal;

 let e1: Literal = "as\0df".parse()?;
 let e2 = Literal::new("as\0df")?;
 assert_eq!(e1, e2);

Implementations

impl Literal

pub fn as_bytes(&self) -> &[u8]

Reference the underlying bytes. This wrapper does not allocate any null terminator.

 let e = vectorscan::expression::Literal::new("as\0df")?;
 assert_eq!(e.as_bytes(), b"as\0df");

pub fn new(x: impl Into<Vec<u8>>) -> Result<Self, VectorscanCompileError>

Wrap a byte slice to be interpreted literally. This does not allocate any null terminator.

pub fn compile( &self, flags: Flags, mode: Mode ) -> Result<Database, VectorscanCompileError>

Call Database::compile_literal() with None for the platform.

Trait Implementations

impl Clone for Literal

fn clone(&self) -> Literal

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Literal

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

Formats the value using the given formatter.

impl Display for Literal

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

Formats the value using the given formatter.

impl FromStr for Literal

type Err = VectorscanCompileError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for Literal

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Literal

fn cmp(&self, other: &Literal) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for Literal

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Literal

fn partial_cmp(&self, other: &Literal) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Literal

impl StructuralEq for Literal

impl StructuralPartialEq for Literal