hush 0.1.4

Hush is a unix shell scripting language based on the Lua programming language
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pub mod ast;
pub mod error;
pub mod lexer;
pub mod parser;
mod fmt;
mod source;
#[cfg(test)]
mod tests;

use std::cell::RefCell;

use crate::symbol;
pub use ast::Ast;
pub use error::{Error, Errors};
use lexer::Lexer;
use parser::Parser;
pub use source::{Source, SourcePos};
pub use fmt::AnalysisDisplayContext;


/// Syntactical analysis.
#[derive(Debug)]
pub struct Analysis {
	/// The produced AST, possibly partial if there were errors.
	pub ast: Ast,
	/// Syntax errors.
	pub errors: Errors,
}


impl Analysis {
	/// Perform syntax analysis in the given source.
	pub fn analyze(source: &Source, interner: &mut symbol::Interner) -> Self {
		let cursor = lexer::Cursor::from(source);
		let lexer = Lexer::new(cursor, interner);

		// Errors will be produced by the lexer and the parser alternatively.
		// There won't be borrow issues here because the lexer will always run a complete
		// iteration (producing a token or an error) before yielding to the parser.
		let errors = RefCell::new(Vec::new());

		let tokens = lexer.filter_map(|result| match result {
			Ok(token) => Some(token),
			Err(error) => {
				errors.borrow_mut().push(Error::Lexer(error));
				None
			}
		});

		let parser = Parser::new(tokens, |error| {
			errors.borrow_mut().push(Error::Parser(error))
		});

		let statements = parser.parse();

		Analysis {
			ast: Ast {
				source: source.path,
				statements
			},
			errors: Errors(errors.into_inner().into()),
		}
	}


	/// Check if no errors occurred.
	pub fn is_ok(&self) -> bool {
		self.errors.is_empty()
	}
}