The marlowe-object package is an extension of @marlowe.io/language-core-v1 that allows for referencing Party, Value, Observation, Token, Contract, and Action types in a bundle. This approach flattens the tree structure a bit and allows reusability.
This package exposes a main module with the extended constructs and two modules to bundle them, bundle-list and bundle-map. Both bundle types provide the same information but are useful in different contexts. ContractBundleList is the type expected by the runtime and is used in the createContractSources of the @marlowe.io/runtime-rest-client package. On the other hand, ContractBundleMap is more ergonomic for developers as it is order-independent and is used when creating source maps to have O(1) access. You can convert between the different bundle types using bundleMapToList or bundleListToMap.
While you can manually define a contract using ContractBundleList or ContractBundleMap, the primary intention of this package is to serve as the output of a higher-level abstraction, potentially even a new language that compiles to Marlowe. The name marlowe-object is inspired by the .o files generated when you compile a .c file, with createContractSources acting as a linker.
This package also simplifies the creation of large contracts. A Marlowe contract is a Tree structure, and if the tree is big enough it won't fit on the blockchain. To solve that, the Marlowe Core specification has a concept called Merkleization, which represents large contracts as a Merkle tree's. The splitting and hashing of a large contract into a Merkle Tree is done through the runtime calls (createContractSources), and we use marlowe-object to define the large contract in a more approachable way.
The marlowe-object package also extends the core types with the ability to annotate contract nodes. This can simplify UI development by tagging nodes with information that can be used to infere a logical state and also allow source mapping from a higer level language.
