HQL

HQL, the Hyper Query Language, is a statically typed expression and query language. It combines functional expressions with pipelines over files, streams, structured data and HyperMarkDown documents, and checks a program's types before it evaluates it.

type Book { title : String, year : Int, rating : Int }

books = [
    Book(title = "Dune", year = 1965, rating = 5),
    Book(title = "Emma", year = 1815, rating = 3),
    Book(title = "Beloved", year = 1987, rating = 4),
]

books
| filter(b => b.rating >= 4)
| sort(b => b.title)
| map(b => b.title)

["Beloved", "Dune"]

source reads the documents a file holds, and target writes a value to one:

source(file("sightings.jsonl"), Json)
| filter(s => s.seen == "morning")
| target(file("morning.json"))

• Install — a release binary or cargo install hql.
• Learn HQL — the book, one runnable program at a time.
• Reference — the grammar, the command line, and reporting.