Script Types

There are three types of scripts:

• dApp script enables you to define сallable functions that can be called from other accounts by the Invoke Script transaction, accept payments to the dApp and perform various actions on the blockchain. Also dApp script can comprise a verifier function that allows or denies transactions and orders that are sent on behalf of the dApp account.
• Account script allows or denies transactions and orders that are sent on behalf of the account (like a verifier function of a dApp script).
• Asset script allows or denies transactions involving the asset.

Features of each script type are described in the table.

#	dApp script	Account script	Asset script
Directives	{-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-}	{-# CONTENT_TYPE EXPRESSION #-} {-# SCRIPT_TYPE ACCOUNT #-}	{-# CONTENT_TYPE EXPRESSION #-} {-# SCRIPT_TYPE ASSET #-}
Content	Set of definitions	Boolean expression	Boolean expression
this variable	Address structure containing dApp address	Address structure containing smart account address	Asset structure
Transaction or order that is checked	Check is performed by the verifier function only. Annotation of the function sets the name of the variable that contains the outgoing transaction or the order, for example: @Verifier(tx)	Built-in variable tx: Transaction|Order contains the outgoing transaction or the order	Build-in variable tx: Transaction contains the transaction involving the asset. Order check is not supported
Proofs accessibility	• Proofs of the outgoing transaction or the order are accessible to the verifier function. • Proofs of the invoke script transaction are inaccessible to the callable function	Accessible	Inaccessible
Blockchain data	• Accessible to the callable function • Accessible to the verifier function when checking a transaction • Inaccessible to the verifier function when checking an order	• Accessible when checking a transaction • Inaccessible when checking an order	Accessible