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API

New types

type chest

A type for chests

type chest_key

A type for chest keys

type chest_opening_result = ["Ok_opening", bytes] | ["Fail_decrypt"] | ["Fail_timelock"];

A type for the result of chest opening, see Tezos.open_chest

New primitives

Tezos

let open_chest : chest_key => chest => nat => chest_opening_result

let call_view : string => 'arg => address => option <'ret>

let constant : string => 'a

Test

New signature for originate_from_file:

let originate_from_file = (filepath: string, entrypoint: string , views : list <'string> , init: michelson_program, balance: tez) => [address, michelson_program, int]

Originate a contract with a path to the contract file, an entrypoint, a list of views, an initial storage and an initial balance.

let create_chest : bytes => nat => [chest , chest_key]

Generate a locked value, the RSA parameters and encrypt the payload. Also returns the chest key Exposes tezos timelock library function create_chest_and_chest_key

let create_chest_key : chest => nat => chest_key

Unlock the value and create the time-lock proof. Exposes tezos timelock library function create_chest_key.

Examples

Timelock

Extensive documentation about timelock can be found here. Here is an example of a contract trying to open a chest and the corresponding tests to trigger all error kinds:

let open_or_fail = ([ck, c, @time] : [chest_key, chest, nat]) : bytes => {

return (match ( Tezos.open_chest(ck,c,@time), {

Ok_opening: (b:bytes) => b,

Fail_decrypt: () => failwith("decrypt"),

Fail_timelock: () => failwith("timelock"),

}))

};

On-chain views

Tezos documentation on views can be found here

On-chain views are named routines attached to your contract allowing another contract to call them to get a "view" of your contract current storage. It cannot modify your storage nor emit operations. These routines can either simply return your contract storage or apply some kind of processing to it: they take your current storage, a parameter and returns the data of your choice. Note that parameter and return types can be anything except big_map; sapling_state ; operation and ticket. Views are named after their declaration name and can be compiled in two ways:

1. by passing their names to the command line option --views (e.g. ligo compile contract --views v1,v2,v3)

2. by annotating their declarations in your code with view

Important: the first way (--views) will override any annotated declarations

Given a very simple contract having a storage of type string, here are a few legit views:

type storage = string

let main = ([_ , s]: [unit , storage]) : [ list<operation> , storage] => [list([]), s];

/* view 'view1', simply returns the storage */

@view

let view1 = ([_ , s]: [unit , storage]) : storage => s;

/* view 'v2', returns true if the storage has a given length */

@view

let v2 = ([expected_length,s] : [nat , storage]) : bool => (String.length (s) == expected_length);

/* view 'view3' returns a constant int */

@view

let view3 = ([_ , _s]: [unit , storage]) : int => 42;

Note: [@view] attribute is only supported for top-level functions.

The use of [@view] attribute anywhere other than top-level will be ignored.

A few primitives have a slightly different meaning when executed as part of a view:

• Tezos.get_balance represents the current amount of mutez held by the contract attached to the view
• Tezos.get_sender represents the caller of the view
• Tezos.get_amount is always 0 mutez
• Tezos.get_self_address represents the contract attached to the view

On the caller side, the primitive Tezos.call_view will allow you to call another contract view and get its result by providing the view name; the contract address and the parameter of the view. If the address is nonexistent; the name does not match of of the contract view or the parameter type do not match, Tezos.call_view will return None.

let view_call = ([name,parameter,addr]: [string , int , address]) : option<int> => Tezos.call_view ("sto_plus_n", 1, addr)

Global constant

The new primitive Tezos.constant allows you to use a predefined constant already registered on chain. It accepts a hash in the form of a string and will require a type annotation.