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| -rw-r--r-- | vendor/pest_meta/_README.md | 43 |
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diff --git a/vendor/pest_meta/_README.md b/vendor/pest_meta/_README.md index f91188ccb..da30ab74e 100644 --- a/vendor/pest_meta/_README.md +++ b/vendor/pest_meta/_README.md @@ -5,8 +5,8 @@ # pest. The Elegant Parser -[](https://gitter.im/dragostis/pest?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) -[](https://pest-parser.github.io/book) +[](https://gitter.im/pest-parser/pest?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) +[](https://pest.rs/book) [](https://docs.rs/pest) [](https://github.com/pest-parser/pest/actions/workflows/ci.yml) @@ -31,25 +31,28 @@ Other helpful resources: * API reference on [docs.rs] * play with grammars and share them on our [fiddle] -* leave feedback, ask questions, or greet us on [Gitter] +* find previous common questions answered or ask questions on [GitHub Discussions] +* leave feedback, ask questions, or greet us on [Gitter] or [Discord] -[book]: https://pest-parser.github.io/book +[book]: https://pest.rs/book [docs.rs]: https://docs.rs/pest -[fiddle]: https://pest-parser.github.io/#editor -[Gitter]: https://gitter.im/dragostis/pest +[fiddle]: https://pest.rs/#editor +[Gitter]: https://gitter.im/pest-parser/pest +[Discord]: https://discord.gg/XEGACtWpT2 +[GitHub Discussions]: https://github.com/pest-parser/pest/discussions ## Example The following is an example of a grammar for a list of alphanumeric identifiers -where the first identifier does not start with a digit: +where all identifiers don't start with a digit: ```rust alpha = { 'a'..'z' | 'A'..'Z' } digit = { '0'..'9' } -ident = { (alpha | digit)+ } +ident = { !digit ~ (alpha | digit)+ } -ident_list = _{ !digit ~ ident ~ (" " ~ ident)+ } +ident_list = _{ ident ~ (" " ~ ident)* } // ^ // ident_list rule is silent which means it produces no tokens ``` @@ -81,6 +84,9 @@ thread 'main' panicked at ' --> 1:1 = expected ident', src/main.rs:12 ``` +These error messages can be obtained from their default `Display` implementation, +e.g. `panic!("{}", parser_result.unwrap_err())` or `println!("{}", e)`. + ## Pairs API The grammar can be used to derive a `Parser` implementation automatically. @@ -133,6 +139,25 @@ Letter: b Digit: 2 ``` +### Defining multiple parsers in a single file +The current automatic `Parser` derivation will produce the `Rule` enum +which would have name conflicts if one tried to define multiple such structs +that automatically derive `Parser`. One possible way around it is to put each +parser struct in a separate namespace: + +```rust +mod a { + #[derive(Parser)] + #[grammar = "a.pest"] + pub struct ParserA; +} +mod b { + #[derive(Parser)] + #[grammar = "b.pest"] + pub struct ParserB; +} +``` + ## Other features * Precedence climbing |