Struct regex::RegexBuilder

pub struct RegexBuilder(_);

A configurable builder for a regular expression.

A builder can be used to configure how the regex is built, for example, by setting the default flags (which can be overridden in the expression itself) or setting various limits.

Methods

impl RegexBuilder

fn new(pattern: &str) -> RegexBuilder

Create a new regular expression builder with the given pattern.

If the pattern is invalid, then an error will be returned when compile is called.

fn compile(self) -> Result<Regex, Error>

Consume the builder and compile the regular expression.

Note that calling as_str on the resulting Regex will produce the pattern given to new verbatim. Notably, it will not incorporate any of the flags set on this builder.

fn case_insensitive(self, yes: bool) -> RegexBuilder

Set the value for the case insensitive (i) flag.

fn multi_line(self, yes: bool) -> RegexBuilder

Set the value for the multi-line matching (m) flag.

fn dot_matches_new_line(self, yes: bool) -> RegexBuilder

Set the value for the any character (s) flag, where in . matches anything when s is set and matches anything except for new line when it is not set (the default).

N.B. "matches anything" means "any byte" for regex::bytes::Regex expressions and means "any Unicode codepoint" for regex::Regex expressions.

fn swap_greed(self, yes: bool) -> RegexBuilder

Set the value for the greedy swap (U) flag.

fn ignore_whitespace(self, yes: bool) -> RegexBuilder

Set the value for the ignore whitespace (x) flag.

fn unicode(self, yes: bool) -> RegexBuilder

Set the value for the Unicode (u) flag.

For byte based regular expressions, this is disabled by default.

fn size_limit(self, limit: usize) -> RegexBuilder

Set the approximate size limit of the compiled regular expression.

This roughly corresponds to the number of bytes occupied by a single compiled program. If the program exceeds this number, then a compilation error is returned.

fn dfa_size_limit(self, limit: usize) -> RegexBuilder

Set the approximate size of the cache used by the DFA.

This roughly corresponds to the number of bytes that the DFA will use while searching.

Note that this is a per thread limit. There is no way to set a global limit. In particular, if a regex is used from multiple threads simulanteously, then each thread may use up to the number of bytes specified here.