# Abella DAMF

Abella DAMF is a branch of the Abella theorem prover that is designed to use and publish DAMF assertions.

### Obtaining and Building

You need a working OCaml distribution with some standard accompanying software such as OPAM, Dune, and findlib. The instructions below are for a recent OCaml (≥4.14.0) and OPAM (≥2.1.2).

1. Clone the Abella repository:
% git clone https://github.com/abella-prover/abella.git

2. From the abella directory, run these commands:
% git checkout ipfs
% opam pin -y .

This pin will override (reversibly) the existing Abella package in OPAM if any, then build and install Abella to your OPAM environment. You can then launch Abella through the command $(opam var bin)/abella – or just abella if you have set up your OPAM environment correctly. %$(opam var bin)/abella -v
2.0.9-ipfs

3. To uninstall this version of Abella and restore the standard Abella packages in OPAM, run in the same abella directory as step 2 above:
% opam uninstall -y abella
% opam unpin .


### Using

1. Limitations:
• Abella DAMF only runs in batch mode, i.e., it can only process a single .thm file at a time in a non-interactive session.
• Abella DAMF currently does not support the specification language. In other words, you cannot use the Specification command. This limitation will be relaxed soon. All other features of the reasoning language of Abella are supported.
2. Prerequisite: you must setup Dispatch. In particular:
• You will need to know the path to the Dispatch executable.
• You will need to create, at minimum, an agent profile using dispatch create-agent.
3. Place the following in $XDG_CONFIG_HOME/abella/config.json (creating the containing directory if it doesn’t exist). If $XDG_CONFIG_HOME is not defined in your environment, use \$HOME/.config/abella/config.json instead.
{
"damf.dispatch": "/path/to/dispatch-executable",
"damf.agent": "agent-profile-name"
}

Replace the values with the path to the Dispatch executable and the name of your agent profile you created in step 2.
4. DAMF mode is enabled with the following switches:
• --damf-imports: this will enable the Import "damf:..." top-level command.
• --damf-publish DEST: to enable publishing DAMF assertions signed with your agent profile. DEST is one of the following:
• local (for your local IPFS store, managed by whichever IPFS daemon you use, e.g., Kupo)
• cloud (for publishing through web3.storage; see the Dispatch documentation for details)