Struct regex_syntax::hir::translate::TranslatorBuilder

pub struct TranslatorBuilder {
    utf8: bool,
    line_terminator: u8,
    flags: Flags,
}

A builder for constructing an AST->HIR translator.

Fields

utf8: bool

line_terminator: u8

flags: Flags

Implementations

impl TranslatorBuilder

pub fn new() -> TranslatorBuilder

Create a new translator builder with a default c onfiguration.

pub fn build(&self) -> Translator

Build a translator using the current configuration.

pub fn utf8(&mut self, yes: bool) -> &mut TranslatorBuilder

When disabled, translation will permit the construction of a regular expression that may match invalid UTF-8.

When enabled (the default), the translator is guaranteed to produce an expression that, for non-empty matches, will only ever produce spans that are entirely valid UTF-8 (otherwise, the translator will return an error).

Perhaps surprisingly, when UTF-8 is enabled, an empty regex or even a negated ASCII word boundary (uttered as (?-u:\B) in the concrete syntax) will be allowed even though they can produce matches that split a UTF-8 encoded codepoint. This only applies to zero-width or “empty” matches, and it is expected that the regex engine itself must handle these cases if necessary (perhaps by suppressing any zero-width matches that split a codepoint).

pub fn line_terminator(&mut self, byte: u8) -> &mut TranslatorBuilder

Sets the line terminator for use with (?u-s:.) and (?-us:.).

Namely, instead of . (by default) matching everything except for \n, this will cause . to match everything except for the byte given.

If . is used in a context where Unicode mode is enabled and this byte isn’t ASCII, then an error will be returned. When Unicode mode is disabled, then any byte is permitted, but will return an error if UTF-8 mode is enabled and it is a non-ASCII byte.

In short, any ASCII value for a line terminator is always okay. But a non-ASCII byte might result in an error depending on whether Unicode mode or UTF-8 mode are enabled.

Note that if R mode is enabled then it always takes precedence and the line terminator will be treated as \r and \n simultaneously.

Note also that this doesn’t impact the look-around assertions (?m:^) and (?m:$). That’s usually controlled by additional configuration in the regex engine itself.

pub fn case_insensitive(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the case insensitive flag (i) by default.

pub fn multi_line(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the multi-line matching flag (m) by default.

pub fn dot_matches_new_line(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the “dot matches any character” flag (s) by default.

pub fn crlf(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the CRLF mode flag (R) by default.

pub fn swap_greed(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the “swap greed” flag (U) by default.

pub fn unicode(&mut self, yes: bool) -> &mut TranslatorBuilder

Enable or disable the Unicode flag (u) by default.

Trait Implementations

impl Clone for TranslatorBuilder

fn clone(&self) -> TranslatorBuilder

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TranslatorBuilder

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

Formats the value using the given formatter.

impl Default for TranslatorBuilder

fn default() -> TranslatorBuilder

Returns the “default value” for a type.