feat: Add new tket-qec crate with Iceberg code extension.

.github/change-filters.yml

@@ -12,6 +12,7 @@ rust:
   - "badger-optimiser/**"
   - "compile-rewriter/**"
   - "tket1-passes/**"
+  - "tket-qec/**"
 
 python:
   - *rust-core

Cargo.toml

@@ -11,6 +11,7 @@ members = [
     "tket-qsystem",
     "tket1-passes",
     "qis-compiler",
+    "tket-qec",
 ]
 default-members = ["tket", "tket-qsystem"]
 

tket-qec/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name = "tket-qec"
+version = "0.1.0"
+edition.workspace = true
+rust-version.workspace = true
+
+license.workspace = true
+readme = "README.md"
+# documentation = "https://docs.rs/tket-qec"
+homepage.workspace = true
+repository.workspace = true
+description = "HUGR extensions for logical operations on QEC codes."
+keywords = ["Quantum", "Quantinuum"]
+categories = ["compilers"]
+
+[lints]
+workspace = true
+
+[dependencies]
+hugr.workspace = true
+semver = "1.0.27"
+strum = { workspace = true, features = ["derive"] }
+tket-qsystem = { version = "0.23.0", path = "../tket-qsystem" }

tket-qec/README.md

@@ -0,0 +1,9 @@
+# tket-qec
+
+HUGR extensions for logical operations on QEC codes.
+
+## License
+
+This project is licensed under Apache License, Version 2.0 ([LICENSE][] or <http://www.apache.org/licenses/LICENSE-2.0>).
+
+  [LICENSE]: https://github.com/quantinuum/tket2/blob/main/LICENCE

tket-qec/src/iceberg.rs

@@ -0,0 +1,47 @@
+//! HUGR extension for logical operations on the Iceberg code.
+//!
+//! The extension `tket.qec.iceberg.types` provides one new type: this is the
+//! code block for the [[k+2, k, 2]] Iceberg code (parametrized by an even
+//! integer k >= 2). This is a linear (non-copyable) type.
+//!
+//! ```
+//! use tket_qec::iceberg::types::block_type;
+//!
+//! let block = block_type(6);
+//! assert!(!block.copyable());
+//! ```
+//!
+//! The extension `tket.qec.iceberg.ops` provides operations that act on this
+//! block type.
+//!
+//! To allocate a new block, with all (logical) qubits initialized to zero, use
+//! an `alloc_zero` operation. This is parametrized by k (the number of logical
+//! qubits):
+//!
+//! ```
+//! use tket_qec::iceberg::ops::EXTENSION;
+//!
+//! let alloczero = EXTENSION
+//!     .instantiate_extension_op("alloc_zero", [8.into()])
+//!     .unwrap();
+//! ```
+//!
+//! Use the `free` operation to free a previously allocated block.
+//!
+//! Some of the operations (such as `all_x` or `cx_transverse`) operate purely
+//! at the block level. Others (such as `x` or `cx`) take one or more indices
+//! as parameters: these are (64-bit unsigned) integers less than `k`, which
+//! address logical qubits within the block. Some operations also take an angle,
+//! represented as a float in radians.
+//!
+//! All operations that take indices come in two versions, "static" and
+//! "dynamic", depending on whether the indices are parameters to the operation
+//! itself (in which case they must be statically known) or dynamic (in which
+//! case they are integer inputs to the operation). The dynamic versions have
+//! names ending in `_d`. For example, `x_d` takes a block and an integer as
+//! inputs, and outputs the block. Note that whereas the static versions are
+//! infallible (validity of indices is checked on construction), the dynamic
+//! versions will panic if the indices are invalid.
+
+pub mod ops;
+pub mod types;