Source code for qbraid.transpiler.conversions.qasm3.qasm3_to_qiskit

# Copyright 2025 qBraid
#
# 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,
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"""
Module defining Qiskit OpenQASM conversions

"""
from __future__ import annotations

from typing import TYPE_CHECKING

from qbraid_core._import import LazyLoader

from qbraid.passes.qasm.compat import add_stdgates_include, insert_gate_def, replace_gate_names
from qbraid.transpiler.annotations import weight

qiskit_qasm3 = LazyLoader("qiskit_qasm3", globals(), "qiskit.qasm3")


if TYPE_CHECKING:
    import qiskit as qiskit_

    from qbraid.programs.typer import Qasm3StringType


def transform_notation(qasm3: str) -> str:
    """
    Process an OpenQASM 3 program that was generated by
    an external tool to make it compatible with Qiskit.

    """
    replacements = {
        "cnot": "cx",
        "si": "sdg",
        "ti": "tdg",
        "v": "sx",
        "vi": "sxdg",
        "phaseshift": "p",
        "cphaseshift": "cp",
    }

    qasm3 = replace_gate_names(qasm3, replacements)
    qasm3 = add_stdgates_include(qasm3)
    qasm3 = insert_gate_def(qasm3, "iswap")
    qasm3 = insert_gate_def(qasm3, "sxdg")

    return qasm3


[docs] @weight(1) def qasm3_to_qiskit(qasm: Qasm3StringType) -> qiskit_.QuantumCircuit: """Convert QASM 3.0 string to a Qiskit QuantumCircuit representation. Args: qasm (str): A string in QASM 3.0 format. Returns: qiskit.QuantumCircuit: A QuantumCircuit object representing the input QASM 3.0 string. """ try: return qiskit_qasm3.loads(qasm) except qiskit_qasm3.QASM3ImporterError: pass qasm = transform_notation(qasm) return qiskit_qasm3.loads(qasm)