Crate kailua_syntax [−] [src]

AST and parser for Kailua.

Kailua parses a single source file in this order:

  1. The file contents are read into kailua_env::Source in the caller-dependent manner. This step is flexible enough that the caller is free to make the contents up. Source emits a single span for the entire file.

  2. The lexer (kailua_syntax::lex::Lexer) receives the span and Source and yields a list of tokens (kailua_syntax::lex::Tok) with the associated span.

    Tokens produced by the lexer include ordinary Lua tokens, Kailua-specific meta comments (e.g. --# = DashDashHash), newlines at the end of meta comments, normal comments and the end of file. Therefore they are sufficient for highlighting any Lua or Kailua code.

    Later steps rely on Kailua-specific tokens to produce Kailua-specific AST nodes. Care should be taken when tokens are generated by the other means.

  3. The nesting analyzer (kailua_syntax::lex::Nest) adds additional informations to the spanned tokens so that the parser can recover from errors.

    The "nesting" is roughly a range of tokens that should be skipped on a parsing error. The nesting can be, well, nested and roughly gives an outline of the source code.

    The resulting tokens with nesting informations (kailua_syntax::lex::NestedToken) have no actual information about the nesting. Instead, the compact data to distinguish different nestings are calculated and recorded.

  4. The parser (kailua_syntax::Parser) converts a series of tokens with nesting informations into the chunk (kailua_syntax::ast::Chunk).

    The chunk also contains a list of spanned scopes, names in each scope, globally assigned names and additional hints for each token. This allows for basic analyses without even touching the type checker.

Reexports

pub use string::Str;
pub use string::Name;
pub use lex::Tok;
pub use ast::Chunk;

Modules

ast

The abstract syntax tree (AST).
lang

Source language description.
lex

Lexical analysis.
string

Common string-like types and routines.

Structs

Lexer

The lexical analyzer.
Nest

The nesting analyzer.
NestedToken

A token with the nesting information.
Parser

The parser.

Functions

parse_chunk

An one-off function to parse a chunk from a given span in the Source.