DAML Script Library

The DAML Script library defines the API used to implement DAML scripts. See DAML Script:: for more information on DAML script.

Module Daml.Script

Data Types

data Commands a

This is used to build up the commands send as part of submit. If you enable the ApplicativeDo extension by adding {-# LANGUAGE ApplicativeDo #-} at the top of your file, you can use do-notation but the individual commands must not depend on each other.

instance Functor Commands

instance HasSubmit Script Commands

instance Applicative Commands

instance HasField “commands” (SubmitCmd a) (Commands a)

instance HasField “commands” (SubmitMustFailCmd a) (Commands a)

data ParticipantName

ParticipantName

Field	Type	Description
participantName	Text

instance HasField “participantName” ParticipantName Text

data PartyDetails

The party details returned by the party management service.

PartyDetails

Field	Type	Description
party	Party	Party id
displayName	Optional Text	Optional display name
isLocal	Bool	True if party is hosted by the backing participant.

instance Eq PartyDetails

instance Ord PartyDetails

instance Show PartyDetails

instance HasField “continue” (ListKnownPartiesPayload a) ([PartyDetails] -> a)

instance HasField “displayName” PartyDetails (Optional Text)

instance HasField “isLocal” PartyDetails Bool

instance HasField “party” PartyDetails Party

data PartyIdHint

A hint to the backing participant what party id to allocate. Must be a valid PartyIdString (as described in @value.proto@).

PartyIdHint

Field	Type	Description
partyIdHint	Text

instance HasField “partyIdHint” PartyIdHint Text

data Script a

This is the type of A DAML script. Script is an instance of Action, so you can use do notation.

instance Functor Script

instance CanAbort Script

instance HasSubmit Script Commands

instance HasTime Script

instance Action Script

instance ActionFail Script

instance Applicative Script

instance HasField “runScript” (Script a) (() -> Free ScriptF (a, ()))

Functions

query

: Template t => Party -> Script [(ContractId t, t)]

Query the set of active contracts of the template that are visible to the given party.

queryContractId

: Template t => Party -> ContractId t -> Script (Optional t)

Query for the contract with the given contract id.

Returns None if there is no active contract the party is a stakeholder on. This is semantically equivalent to calling query and filtering on the client side.

setTime

: Time -> Script ()

Set the time via the time service.

This is only supported in static time mode when running over the gRPC API.

Note that the ledger time service does not support going backwards in time. However, you can go back in time in DAML Studio.

passTime

: RelTime -> Script ()

Advance ledger time by the given interval.

Only supported in static time mode when running over the gRPC API and in DAML Studio. Note that this is not an atomic operation over the gRPC API so no other clients should try to change time while this is running.

Note that the ledger time service does not support going backwards in time. However, you can go back in time in DAML Studio.

allocateParty

: Text -> Script Party

Allocate a party with the given display name using the party management service.

allocatePartyWithHint

: Text -> PartyIdHint -> Script Party

Allocate a party with the given display name and id hint using the party management service.

allocatePartyOn

: Text -> ParticipantName -> Script Party

Allocate a party with the given display name on the specified participant using the party management service.

allocatePartyWithHintOn

: Text -> PartyIdHint -> ParticipantName -> Script Party

Allocate a party with the given display name and id hint on the specified participant using the party management service.

listKnownParties

: Script [PartyDetails]

List the parties known to the default participant.

listKnownPartiesOn

: ParticipantName -> Script [PartyDetails]

List the parties known to the given participant.

sleep

: RelTime -> Script ()

Sleep for the given duration.

This is primarily useful in tests where you repeatedly call query until a certain state is reached.

Note that this will sleep for the same duration in both wallcock and static time mode.

createCmd

: Template t => t -> Commands (ContractId t)

Create a contract of the given template.

exerciseCmd

: Choice t c r => ContractId t -> c -> Commands r

Exercise a choice on the given contract.

exerciseByKeyCmd

: (TemplateKey t k, Choice t c r) => k -> c -> Commands r

Exercise a choice on the contract with the given key.

createAndExerciseCmd

: Choice t c r => t -> c -> Commands r

Create a contract and exercise a choice on it in the same transacton.

archiveCmd

: Choice t Archive () => ContractId t -> Commands ()

Archive the given contract.

archiveCmd cid is equivalent to exerciseCmd cid Archive.

script

: Script a -> Script a

Convenience helper to declare you are writing a Script.

This is only useful for readability and to improve type inference. Any expression of type Script a is a valid script regardless of whether it is implemented using script or not.