Notepad/enter/Machine Tips (Quantum)/Resources/Code & Circuit Operations/Languages/LISP/QuiL.md

Quil

QuiL is the classic example of a language written specifically for a quantum machine.

The full document on the Quil language is found here.

Quil Specification

Authors: Robert S. Smith; Rigetti & Co. Inc.; and contributors

Language Version: 2021.1 (DRAFT)

Table of Contents

• 1. Preamble
• 1.1. An Introduction to Quil
• 1.2. Annexes
• 2. Operational Semantic Devices
• 2.1. Mathematical Preliminaries
• 2.2. The Quantum Abstract Machine
• 3. Structure of a Quil Program
• 3.1. Meta-Syntax
• 3.2. Syntactic Rudiments
• 3.2.1. Arithmetic Expressions
• 3.3. Main Program Elements
• 3.4. Comments
• 4. Quantum Gates
• 4.1. Qubits and Quantum State
• 4.2. Quantum Gate Definitions
• 4.2.1. Structure of a Gate Definition
• 4.2.2. Definition by Matrix
• 4.2.3. Definition by Permutation
• 4.2.4. Definition by Pauli Sum
• 4.2.4.1. Semantics
• 4.2.4.2. Example Syntax
• 4.2.4.3. Example Semantic Reduction of CPHASE
• 4.3. Standard Gate Definitions
• 4.3.1. Pauli Gates
• 4.3.2. Hadamard Gate
• 4.3.3. Phase Gates
• 4.3.4. Controlled-Phase Gates
• 4.3.5. Cartesian Rotation Gates
• 4.3.6. Controlled-X Gates
• 4.3.7. Swap Gates
• 4.3.8. Other Gates
• 4.4. Quantum Gate Applications
• 4.4.1. Syntax and Semantics
• 4.4.2. DAGGER Gate Modifier
• 4.4.3. CONTROLLED Gate Modifier
• 4.4.4. FORKED Gate Modifier
• 4.4.5. Chaining Modifiers
• 5. Quantum State Reset
• 6. Classical Memory
• 6.1. Design Considerations
• 6.2. Types
• 6.3. Declaring Memory
• 6.3.1. Declaring Memory
• 6.3.2. Declaring Aliased Memory
• 6.3.3. Declaring Aliased Memory Declaration with an Offset
• 6.3.4. Portability of Aliased Declarations
• 6.3.5. Duplicate Declaration Identifiers
• 6.3.6. Examples
• 6.3.6.1. Register Machine with a Condition Bit
• 6.3.6.2. Memory-Mapped RAM
• 6.3.6.3. Computing Bits of an Angle
• 6.4. Memory Access and Dereferencing
• 6.5. Classical Instructions
• 7. Measurement
• 8. Classical Control
• 8.1. Halting the Program
• 8.2. Program Labels and Branching
• 9. Other Instructions and Directives
• 9.1. No-Operation Instruction
• 9.2. Pragmas
• 9.3. File Inclusion
• 10. Circuits
• 10.1. Circuit Syntax
• 10.2. Circuit Expansion
• 11. History and Changes
• 11.1. A History of Quil
• 11.2. Changes
• 12. Annex T: Pulse-Level Control
• 12.1. Frames
• 12.1.1. DEFFRAME
• 12.1.1.1. Frame Attributes
• 12.2. Waveforms
• 12.2.1. Defining new waveforms
• 12.3. Pulses
• 12.4. Frame Mutations
• 12.4.1. Frequency
• 12.4.2. Phase
• 12.4.3. Scale
• 12.5. Capture
• 12.6. Defining Calibrations
• 12.7. Timing and Synchronization

Note: This document is in DRAFT STATUS and is for review purposes only. It is being developed by the Quil-Lang group on GitHub.

1. Preamble

1.1. An Introduction to Quil

This is the language specification for Quil, a language for hybrid classical/quantum computations.

TLDR

Quil is an instruction-based language; each line of a Quil program generally corresponds to a single, discrete action. Despite its resemblance, Quil is not an assembly language.

• QVM is what runs on the backend and is the high-performance Quil simulator