panproto-expr-parser

Lexer, parser, and pretty-printer for panproto-expr.

Syntax and implementation

The surface language includes lambdas, application, let, conditionals, pattern matching, records, lists, list comprehensions, literals, and infix operators. The lexer uses logos. It inserts indentation tokens for layout-sensitive constructs. The parser uses chumsky and a Pratt parser for precedence.

pretty_print emits a canonical surface form and inserts parentheses according to the parser's precedence table. Property tests check pretty-print and reparse on generated well-formed expressions. This is a tested invariant over those generators, not a claim that arbitrary malformed source is preserved.

Example

use panproto_expr_parser::{parse, pretty_print, tokenize};

let tokens = tokenize(r#"\x -> x * 2 + 1"#)?;
let expr = parse(&tokens)?;
let rendered = pretty_print(&expr);

Public API

License

MIT