The Apalache Module

Similar to the TLC module, we provide the module called Apalache, which can be found in src/tla. Most of the operators in that modules are introduced internally by Apalache, when it is rewriting a TLA+ specification. It is useful to read the comments to the operators defined in Apalache.tla, as they will help you in understanding the detailed output produced by the tool, see. Perhaps, the most interesting operator in Apalache is the type assignment operator that is defined as follows:

x := e == x = e

See the discussion on the role of assignments in Apalache.