Module parser

plotnik_lib

Module parser 

Source
Expand description

Parser infrastructure for the query language.

§Architecture

This parser produces a lossless concrete syntax tree (CST) via Rowan’s green tree builder. Key design decisions borrowed from rust-analyzer, rnix-parser, and taplo:

  • Zero-copy parsing: tokens carry spans, text sliced only when building tree nodes
  • Trivia buffering: whitespace/comments collected, then attached as leading trivia
  • Checkpoint-based wrapping: retroactively wrap nodes for quantifiers *+?
  • Explicit recovery sets: per-production sets determine when to bail vs consume diagnostics

§Recovery Strategy

The parser is resilient—it always produces a tree. Recovery follows these rules:

  1. Unknown tokens get wrapped in SyntaxKind::Error nodes and consumed
  2. Missing expected tokens emit a diagnostic but don’t consume (parent may handle)
  3. Recovery sets define “synchronization points” per production
  4. On recursion limit, remaining input goes into single Error node

However, fuel exhaustion (exec_fuel, recursion_fuel) returns an actual error immediately.

Re-exports§

pub use cst::SyntaxKind;
pub use cst::SyntaxNode;
pub use cst::SyntaxToken;
pub use ast::AltExpr;
pub use ast::AltKind;
pub use ast::Anchor;
pub use ast::AnonymousNode;
pub use ast::Branch;
pub use ast::CapturedExpr;
pub use ast::Def;
pub use ast::Expr;
pub use ast::FieldExpr;
pub use ast::NamedNode;
pub use ast::NegatedField;
pub use ast::QuantifiedExpr;
pub use ast::Ref;
pub use ast::Root;
pub use ast::SeqExpr;
pub use ast::SeqItem;
pub use ast::Type;
pub use ast::token_src;

Modules§

ast
Typed AST wrappers over CST nodes.
cst
Syntax kinds for the query language.
lexer
Lexer for the query language.

Structs§

ParseResult
Parser
Trivia tokens are buffered and flushed when starting a new node.