Quantum Computation Language

Quantum Computation Language, known as QCL, is one of the earliest implemented programming languages for quantum computers, created by Bernhard Omer to let programmers explore quantum-computing concepts before multi-qubit quantum hardware existed. Its most notable feature is support for user-defined quantum operators and functions, and its syntax and classical data types closely follow the C programming language, so a QCL program can freely combine ordinary classical code with quantum code in the same source file. Because no general-purpose quantum computer was available when QCL was created, its only implementation is an interpreter built around a classically simulated quantum computer, letting a QCL program's quantum operations run as a simulation on conventional hardware rather than real quantum circuits.