QASM TypeScript

OpenQASM, the low-level programming language for quantum circuit specification, implemented in TypeScript.

Language documentation is provided by IBM here.

New in Version 2.0.0

• Support for the OpenQASM 3.0 spec while retaining OpenQASM 2.0 backwards compatability.

Usage

Import the parse function or parseString function from the package.

import { parseFile, parseString } from 'qasm-ts';

parseFile can be called with a file path to a .qasm file. It will parse the file and return the abstract syntax tree representation. parseFile can also take 3 optional parameters:

1. version: A number, OpenQASMVersion, or OpenQASMMajorVersion to specify whether to use the Qasm 2 or 3 lexer/parser (defaults to version 3).
2. verbose: Whether to return verbose objects that includes an extra key for each node's class name (defaults to false).
3. stringify: Whether to stringify and format the return object (defaults to false).

let ast = parseFile("<file-path>");

parseString should be called with a string of QASM code. It will parse the code and return the abstract syntax tree representation. parseString also takes the same optional arguments as parseFile.

let ast = parseString("<qasm-string>");

Example I/O

Input: alignment.qasm (source)

include "stdgates.inc";

stretch g;

qubit[3] q;
barrier q;
cx q[0], q[1];
delay[g] q[2];
U(pi/4, 0, pi/2) q[2];
delay[2*g] q[2];
barrier q;

Output: Abstract Syntax Tree

Run with: const ast = parseFile("./alignment.qasm", 3);.

[
  Include { filename: '"stdgates.inc"' },
  ClassicalDeclaration {
    classicalType: StretchType {},
    identifier: Identifier { name: 'g' },
    initializer: null,
    isConst: false
  },
  QuantumDeclaration {
    identifier: Identifier { name: 'q' },
    size: IntegerLiteral { value: 3 }
  },
  QuantumBarrier { qubits: [ [Identifier] ] },
  QuantumGateCall {
    quantumGateName: Identifier { name: 'cx' },
    qubits: [ [SubscriptedIdentifier], [SubscriptedIdentifier] ],
    parameters: null,
    modifiers: []
  },
  QuantumDelay {
    duration: Identifier { name: 'g' },
    qubits: [ [SubscriptedIdentifier] ]
  },
  QuantumGateCall {
    quantumGateName: Identifier { name: 'U' },
    qubits: [ [SubscriptedIdentifier] ],
    parameters: Parameters { args: [Array] },
    modifiers: []
  },
  QuantumDelay {
    duration: Arithmetic { op: '*', left: [IntegerLiteral], right: [Identifier] },
    qubits: [ [SubscriptedIdentifier] ]
  },
  QuantumBarrier { qubits: [ [Identifier] ] }
]

Source code

Feel free to clone, fork, comment or contribute on GitHub!

Transpiling

tsc src/*.ts --outDir dist

Installing dependencies

npm install

Run Unit Tests, Conformance Tests

npm test

References

The original OpenQASM authors:

• Andrew W. Cross, Lev S. Bishop, John A. Smolin, Jay M. Gambetta "Open Quantum Assembly Language" arXiv:1707.03429.
• Andrew W. Cross, Ali Javadi-Abhari, Thomas Alexander, Niel de Beaudrap, Lev S. Bishop, Steven Heidel, Colm A. Ryan, Prasahnt Sivarajah, John Smolin, Jay M. Gambetta, Blake R. Johnson "OpenQASM 3: A broader and deeper quantum assembly language" arXiv:2104.14722

Another strongly typed implementation from which this project took some inspiration:

• Adam Kelly's Rust QASM Parser

License

Copyright 2019 Marcus Edwards

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at:

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.