BRAT is a functional programming language designed for writing quantum experiments. For an introduction to BRAT, see the extended abstract submitted to PLanQC 2024.
To build BRAT from source, you will need:
- GHC 9.6.4 (can be installed with the
ghcuptool) - The
stackbuild tool for Haskell
Then, navigate to the brat directory and run stack install.
This will add the brat and brat-lsp binaries to ~/.local/bin, and copy configuration for the emacs editor mode to ~/.local/share/brat/.
There is also a plugin for the VS Code editor. To install this, look at vscode/README.md.
By default, the installed brat executable will typecheck a program given as an argument, e.g.:
brat my-program.bratwhich, if my-program typechecks, will print out the parsed versions of the declarations and a list of remaining holes.
The --compile flag can be used to compile the BRAT program to the hugr IR and print the JSON representation to the command line.
There is a tool in the root of the repository called hugr_validator (install by cd hugr_validator && cargo install --path .) which is used to check that the JSON output from BRAT constitutes a valid hugr. This is invoked by:
brat --compile my-program.brat | hugr_validatorThe brat/examples directory contains some examples of BRAT programs.
For example:
- Quantum teleportation: teleportation.brat
- Quantum Fourier transform: teleportation.brat
- Magic State Distillation: magic-state-distillation.brat
- Simple Repeat-Until-Success: rus.brat
- Ising Hamiltonian: ising.brat
This directory also contains tests of syntax features which, while terse, may serve as a reference in the short term. For example:
- unified.brat contains some functional programs
- dollar_kind.brat tests polymorphism over kernel types
- tups.brat tests heterogenous lists
- compjuxt.brat,
brat/examples/composition.bratcontain tests for diagrammatic syntax - pass.brat tests the 'passthrough' (
..) operator - portpulling.brat demonstrates port pulling