OpenQASM 3 feature table

Below is a list of the OpenQASM 3 language features.

For more details on these capabilities, see the OpenQASM 3.X Live Specification .

Features supported by Qiskit

Key:

Feature	Support	Comments
comments	✅
QASM version string	✅
`include`	✅
unicode names	✅
`qubit`	🟡	Only supports physical qubits, and no arrays.
`bit`	✅
`bool`	✅
`int`	✅	Some support for comparisons against integers and casting.
`uint`	❌
`float`	❌
`angle`	❌
`complex`	❌
`const`	❌
`pi`/`π`/`tau`/`τ`/`euler`/`ℇ`	❌
Aliasing: let	❌
register concatenation	❌
casting	🟡	Casting between arrays of bits, int, and bool is supported
`duration`	✅
`durationof`	❌
`ns`/`µs`/`us`/`ms`/`s`/`dt`	✅
`stretch`	❌
`delay`	✅
`barrier`	✅
`box`	❌
Built-in `U`	✅
`gate`	✅	No support for non-basis gates
`gphase`	❌
`ctrl @`/ `negctrl @`	❌
`inv @`	❌
`pow(k) @`	❌
`reset`	✅
`measure`	✅
bit operations	✅
boolean operations	✅
arithmetic expressions	❌
comparisons	✅
`if`	✅
`else`	✅
`else if`	❌
`for` loops	🟡	Discrete sets and negative stepping is not supported.
`while` loops	❌
`continue`	❌
`break`	❌
`return`	❌
`extern`	🟡	Only for certain extern subroutines exposed by systems. It is currently not possible for clients to submit these.
`def` subroutines (classical)	❌
`def` subroutines (quantum)	❌
`input`	❌
`output`	❌

Key:

Feature	Support	Comments
comments	✅
QASM version string	✅
`include`	✅
unicode names	✅
`qubit`	🟡	Only supports physical qubits, and no arrays.
`bit`	✅
`bool`	✅
`int`	✅	Some support for comparisons against integers and casting.
`uint`	❌
`float`	❌
`angle`	❌
`complex`	❌
`const`	❌
`pi`/`π`/`tau`/`τ`/`euler`/`ℇ`	❌
Aliasing: let	❌
register concatenation	❌
casting	🟡	Casting between arrays of bits, int, and bool is supported
`duration`	✅
`durationof`	❌
`ns`/`µs`/`us`/`ms`/`s`/`dt`	✅
`stretch`	❌
`delay`	✅
`barrier`	✅
`box`	❌
Built-in `U`	✅
`gate`	✅	No support for non-basis gates
`gphase`	❌
`ctrl @`/ `negctrl @`	❌
`inv @`	❌
`pow(k) @`	❌
`reset`	✅
`measure`	✅
bit operations	✅
boolean operations	✅
arithmetic expressions	❌
comparisons	✅
`if`	✅
`else`	✅
`else if`	❌
`for` loops	🟡	Discrete sets and negative stepping is not supported.
`while` loops	❌
`continue`	❌
`break`	❌
`return`	❌
`extern`	🟡	Only for certain extern subroutines exposed by systems. It is currently not possible for clients to submit these.
`def` subroutines (classical)	❌
`def` subroutines (quantum)	❌
`input`	❌
`output`	❌

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