Expand description
Raffia is a parser can parse CSS, SCSS, Sass (indented syntax) and Less.
Basic Usage
This crate provides a simple API to get started.
First, create a parser, give it the source code and specify the syntax,
then call the parse method:
use raffia::{ast::Stylesheet, Parser, Syntax};
let mut parser = Parser::new("a {}", Syntax::Css); // syntax can also be `Scss`, `Sass` or `Less`
let result = parser.parse::<Stylesheet>();
match result {
Ok(ast) => {
// parsed successfully
println!("{:#?}", ast);
}
Err(error) => {
// it failed, error message and position can be accessed via `error`
println!("{:#?}", error);
}
}Advanced Usage
More Parser Options
If you need to control more parser options, you can use ParserBuilder.
For example, to collect comments:
use raffia::ParserBuilder;
let mut comments = vec![];
let builder = ParserBuilder::new("/* comment */ a {}").comments(&mut comments);
let mut parser = builder.build();By default, syntax is CSS when using parser builder. You can customize it:
use raffia::{ParserBuilder, Syntax};
let builder = ParserBuilder::new("a {}").syntax(Syntax::Scss);Parse Partial Structure
Sometimes you don’t want to parse a full stylesheet.
Say you only need to parse a qualified rule or even a single declaration.
All you need to do is to update the generics of the parse method.
use raffia::{ast::QualifiedRule, Parser, Syntax};
let mut parser = Parser::new("a {}", Syntax::Css);
parser.parse::<QualifiedRule>();and
use raffia::{ast::Declaration, Parser, Syntax};
let mut parser = Parser::new("color: green", Syntax::Css);
parser.parse::<Declaration>();Not all AST nodes support the usage above;
technically, those nodes that implement Parse trait are supported.
Retrieve Recoverable Errors
There may be some recoverable errors which doesn’t affect on producing AST.
To retrieve those errors, use recoverable_errors.
use raffia::{ast::Stylesheet, Parser, Syntax};
let mut parser = Parser::new("@keyframes kf { invalid {} }", Syntax::Css);
let result = parser.parse::<Stylesheet>();
assert!(result.is_ok());
println!("{:?}", parser.recoverable_errors());Serialization
Produced AST can be serialized by Serde, but this feature is disabled by default.
You need to enable feature serialize manually:
raffia = { version = "*", features = ["serialize"] }
Then you can pass AST to Serde.
Note that Raffia only supports serialization. Deserialization isn’t supported.