Language guide

The language guide is the reference-depth tour of Quon’s source language. It is the canonical starting point for anyone who wants to write Quon rather than just run it: what a Circuit<n, m, d, C> value is, why a qubit is a linear resource consumed exactly once, how |> and par compose, and how the typechecker turns depth bounds and Clifford classifications into compile-time facts instead of runtime hopes.

Who this is for

Programmers who want to understand the language on its own terms — the type system, the constructs, and the rules the compiler enforces — before reading the compiler internals or the cookbook. No prior quantum-framework experience is assumed, but the pages move at reference depth: each construct is defined precisely, with the invariant the typechecker proves around it.

If you are new to quantum computing entirely, the learning track is the gentler on-ramp; it covers the same two ideas — a circuit is a typed value, a qubit is a linear value — in six short lessons before handing off here.

What this covers

The twelve pages below proceed from the smallest complete program to the features that compose in real algorithms:

• Introduction — what Quon is and how a circuit becomes a typed value.
• Circuits and gates — circuit blocks, |>, and the Circuit<n, m, d, C> contract.
• Qubits and registers — linear qubit values, QReg, and tensored/split.
• The linear type system — no-cloning as a compile-time fact.
• Parallel composition — par and the max (not +) depth rule.
• Depth bounds — depth as a verified type-level bound.
• Clifford classification — the Clifford/Universal class in the type.
• The Quantum Monad — run blocks and allocation.
• Measurement and control — measure, Bit, and if feed-forward.
• Borrow blocks — temporary ancilla workspace with a linear debt.
• QEC blocks — error-correction blocks as typed circuit combinators.
• Putting it together — every feature composed in one program.

For the formal language definition, see the Quon specification.

Where to go next

Once the language is familiar, the cookbook walks complete, CI-verified programs that exercise these features end to end, and the architecture pages show what the compiler does with them.

→ Start with Introduction — What is Quon?.