essential-constraint-vm

The Essential constraint checking VM.

lib.rs:

The essential constraint checking implementation.

Checking Predicates

The primary entrypoint for this crate is the check_predicate function which allows for checking a contract of constraints associated with a single predicate against some provided solution data and state slot mutations in parallel.

Checking Individual Constraints

Functions are also exposed for checking constraints individually.

• The exec_bytecode, exec_bytecode_iter and exec_ops functions allow for executing the constraint and returning the resulting Stack.
• The eval_bytecode, eval_bytecode_iter and eval_ops functions are similar to their exec_* counterparts, but expect the top of the Stack to contain a single boolean value indicating whether the constraint was satisfied (0 for false, 1 for true) and returns this value.

Performing a Single Operation

The step_op function (and related step_op_* functions) are exposed to allow for applying a single operation to the given stack. This can be useful in the case of integrating constraint operations in a downstream VM (e.g. the essential state read VM).

Understanding the Assembly

The essential-constraint-asm crate is re-exported as the [asm] module. See [this module's documentation][asm] for information about the expected behaviour of individual operations.