Struct macro_rules_rt::Rule

pub struct Rule { /* private fields */ }

Pair Matcher and Transcriber.

Implementations

impl Rule

pub fn new(from: Matcher, to: Transcriber) -> Result<Self>

Create a new Rule from Matcher and Transcriber.

Returns an error if the meta-variables of Matcher and Transcriber do not match.

pub fn nest(self, yes: bool) -> Self

Specifies whether to apply replacements to metavariable matches. (default is false.)

If false, only the outermost matched range is replaced.

If true, further substitutions are made for the range matched by meta-variables such as $e:expr.

use macro_rules_rt::Rule;

let from = "a + $e:expr".parse()?;
let to   = "b + $e".parse()?;
let input = "a + a + x";
let rule = Rule::new(from, to)?;
let r_nest_no = rule.clone().replace_all(input)?;
let r_nest_yes = rule.nest(true).replace_all(input)?;
assert_eq!(r_nest_no,  "b + a + x");
assert_eq!(r_nest_yes, "b + b + x");

pub fn replace_all(&self, input: &str) -> Result<String>

Replaces all non-overlapping matches in input with the provided transcriber.

Unlike creating TokenStream from str and then calling Rule::replace_all, the original string is preserved as much as possible.

pub fn replace_all_tokens(&self, input: TokenStream) -> TokenStream

Replaces all non-overlapping matches in input with the provided transcriber.

pub fn match_all<'a>(&'a self, input: &'a str) -> Result<MatchAll<'a>>

Replaces all non-overlapping matches in input with the provided transcriber, and returns detailed information.

pub fn apply(&self, input: &str) -> Result<String>

If the entire input matches the entire from, do the conversion. Otherwise, return an error.

pub fn apply_tokens(&self, input: TokenStream) -> Result<TokenStream>

If the entire input matches the entire from, do the conversion. Otherwise, return an error.

Trait Implementations

impl Clone for Rule

fn clone(&self) -> Rule

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Rule

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

Formats the value using the given formatter.