Examples that prove every rule.

Every maintained grammar keeps accept and reject cases in its source with %test. CI runs those cases in isolated processes and requires every production to reduce at least once.

Calculator

Integer arithmetic, precedence by grammar structure, parentheses, and a handwritten lexer.

Open calculator in Playground → View calculator.y source

JSON

Generated lexer rules, conversion actions, recursive objects and arrays, and every JSON value.

Open JSON shape in Playground → View json.y source

CSV

Quoted fields, escaped quotes, row recursion, and generated newline-aware tokenization.

Open a compatible sample in Playground → View csv.y source

INI

Line-oriented scanning, sections, entries, blank lines, and a nested Ruby Hash result.

Open a compatible sample in Playground → View ini.y source

Tiny language

A Lox-scale starting point with variables, assignment, print statements, expressions, and AST execution.

Open extended sample in Playground → View tiny_language.y source

Use the same gate

Add source examples to a grammar and run ibex test --mode=extended --coverage=100 grammar.y.

Gallery instructions →