Tezos

val get_balance : unit -> tez

let get_balance: (_u: unit) => tez

Get the balance for the contract.

let check (p,s : unit * tez) = [], Tezos.get_balance()

let check = (p: unit, s: tez):[list<operation>, tez] =>
  [list([]), Tezos.get_balance()];

val get_now : unit -> timestamp

let get_now: (_u : unit) => timestamp

Returns the current time as a UNIX timestamp.

In LIGO, timestamps are type compatible in operations with integers. This lets you set for instance time constraints for your smart contracts like this:

Examples

24 hours from now

let today         = Tezos.get_now ()
let one_day       = 86_400
let in_24_hrs     = today + one_day
let some_date     = ("2000-01-01t10:10:10Z" : timestamp)
let one_day_later = some_date + one_day

let today         = Tezos.get_now();
let one_day       = 86_400;
let in_24_hrs     = today + one_day;
let some_date     = ("2000-01-01t10:10:10Z" as timestamp);
let one_day_later = some_date + one_day;

24 hours ago

let today     = Tezos.get_now ()
let one_day   = 86_400
let in_24_hrs = today - one_day

let today     = Tezos.get_now();
let one_day   = 86_400;
let in_24_hrs = today - one_day;

Comparing Timestamps

You can also compare timestamps using the same comparison operators as for numbers

let not_tomorrow = (Tezos.get_now () = in_24_hrs)

let not_tomorrow = (Tezos.get_now() == in_24_hrs);

val get_amount : unit -> tez

let get_amount: (_u : unit) => tez

Get the amount of tez provided by the sender to complete this transaction.

let threshold (p : unit) = if Tezos.get_amount () = 100tz then 42 else 0

function threshold (p : unit) {
  if (Tezos.get_amount() == 100tez) return 42 else return 0;
};

val get_sender : unit -> address

let get_sender: (_u : unit) => address

Get the address that initiated the current transaction.

let check (p : unit) = Tezos.get_sender ()

let check = (p : unit) => Tezos.get_sender ();

val address : 'a contract -> address

let address: (contract: contract<'a>) => address

Get the address associated with a value of type contract.

let check (p : key_hash) =
  let c = Tezos.implicit_account p
  in Tezos.address c

let check = (p : key_hash) => {
  let c = Tezos.implicit_account(p);
  return Tezos.address(c);
};

val get_self_address : unit -> address

let get_self_address: (_u : unit) => address

Get the address of the currently running contract.

let check (p : unit) = Tezos.get_self_address ()

let check = (p : unit) => Tezos.get_self_address();

val self : string -> 'a contract

let self: (entrypoint: string) => contract<'a>

Typecast the currently running contract with an entrypoint annotation. If you are using entrypoints, use "%bar" for a constructor "Bar". If you are not using entrypoints: use "%default"

let check (p : unit) = Tezos.self("%default")

let check = (p: unit) => Tezos.self("%default");

val implicit_account : key_hash -> 'a contract

let implicit_account : (_: key_hash) => contract<unit>

Get the default contract associated with an on-chain key-pair. This contract does not execute code, instead it exists to receive tokens on behalf of a key's owner.

See also: http://tezos.gitlab.io/user/glossary.html#implicit-account

let check (kh : key_hash) = Tezos.implicit_account kh

let check = (kh: key_hash) => Tezos.implicit_account(kh);

val get_source : unit -> address

let get_source: (_u : unit) => address

Get the originator (address) of the current transaction. That is, if a chain of transactions led to the current execution get the address that began the chain. Not to be confused with Tezos.get_sender, which gives the address of the contract or user which directly caused the current transaction.

⚠️ There are a few caveats you should keep in mind before using Tezos.get_source over Tezos.get_sender:

1. Tezos.get_source will never be a contract, so if you want to allow contracts (multisigs etc) to operate your contract, you need to use Tezos.get_sender
2. https://vessenes.com/tx-origin-and-ethereum-oh-my/ -- in general it is somewhat unsafe to assume that Tezos.get_source understands everything that is going to happen in a transaction. If Tezos.get_source transfers to a malicious (or sufficiently attackable) contract, that contract might potentially transfer to yours, without Tezos.get_source's consent. So if you are using Tezos.get_source for authentication, you risk being confused. A good historical example of this is bakers paying out delegation rewards. Naive bakers did (and probably still do) just use tezos-client to transfer to whatever KT1 delegates they had, even if those KT1 were malicious scripts.

let check (p : unit) = Tezos.get_source ()

let check = (p : unit) => Tezos.get_source();

val failwith : 'a -> unit

let failwith: (message: 'a) => unit

See failwith

val get_chain_id : unit -> chain_id

let get_chain_id: (_u : unit) => chain_id

Get the identifier of the chain to distinguish between main and test chains.

This is mainly intended to avoid replay attacks between the chains, and can currently only be used together with Bytes.pack and Bytes.unpack.

type storage = bytes

[@entry]
let main (_ignore : unit) (store : storage) =
  let packed = Bytes.pack (Tezos.get_chain_id ()) in
  if (store <> packed) then
    (failwith "wrong chain" : (operation list * storage))
  else
    ([], (packed: storage))

type storage = bytes;

@entry
let main = (_ignore: unit, storage: storage) : [list<operation>, storage] => {
  let packed = Bytes.pack(Tezos.get_chain_id());
  if (storage != packed) {
    return failwith("wrong chain") as [list<operation>, storage];
  } else {
    return [list([]), packed];
  };
};

val transaction : 'param -> mutez -> 'param contract -> operation

let transaction: (action: 'param, amount: mutez, contract: contract<'param>) => operation

Transfer tez to an account, or run code of another smart contract.

To indicate an account, use unit as param.

val create_contract : ('param -> 'storage -> operation list * 'storage) -> key_hash option -> tez -> 'storage -> (operation * address)

let create_contract = (contract: ('param, 'storage) => (list <operation>, 'storage), delegate: option<key_hash>, balance: tez, init: 'storage) => [operation, address]

Construct an operation that originates a contract from a function. The optional argument of type key_hash represents a delegate.

val create_contract_uncurried : ('param * 'storage -> operation list * 'storage) -> key_hash option -> tez -> 'storage -> (operation * address)

let create_contract_uncurried = (contract: ['param, 'storage] => (list <operation>, 'storage), delegate: option<key_hash>, balance: tez, init: 'storage) => [operation, address]

Construct an operation that originates a contract from an uncurried function. The optional argument of type key_hash represents a delegate.

val set_delegate : key_hash option -> operation

let set_delegate: (delegate: option<key_hash>) => operation

Modify the delegate of the current contract.

The operation fails when:

• the delegate is the same as current delegate
• the keyhash is not of a registered delegate

Use None to withdraw the current delegate.

val get_contract_opt : address -> 'param contract option

let get_contract_opt : (a: address) => option<contract<'param>>

Get a contract from an address.

When no contract is found or the contract doesn't match the type, None is returned.

val get_contract_with_error : address -> string -> 'param contract

let get_contract_with_error : (a: address,s: string) => contract<'param>

Get a contract from an address.

When no contract is found, fail with the provided string

val get_entrypoint_opt : string -> address -> 'param contract option

let get_entrypoint_opt: (entrypoint: string, a: address) => option<contract<'param>>

Get a contract from an address and entrypoint.

Entrypoints are written in the form of: %entrypoint.

When no contract is found or the contract doesn't match the type, None is returned.

val get_level : unit -> nat

let get_level : (_u : unit) => nat

Get the current block level.

val min_block_time : unit -> nat

let min_block_time: unit => nat;

Returns the current minimal time between blocks, the value is obtained from the protocol’s minimal_block_delay constant.

val pairing_check : (bls12_381_g1 * bls12_381_g2) list -> bool

let pairing_check: list<[bls12_381_g1, bls12_381_g2]>) => bool

Verify that the product of pairings of the given list of points is equal to 1 in Fq12. Returns true if the list is empty. Can be used to verify if two pairings P1 and P2 are equal by verifying P1 * P2^(-1) = 1. (extracted from Tezos documentation)

val never : never -> 'a

let never: (never: never) => 'a

Eliminate a value of the type never using the instruction NEVER from Michelson.

val get_total_voting_power : unit -> nat

let get_total_voting_power: (_u : unit) => nat

Return the total voting power of all contracts. The total voting power coincides with the sum of the rolls count of every contract in the voting listings. The voting listings is calculated at the beginning of every voting period.

val voting_power : key_hash -> nat

let voting_power: (key_hash:key_hash) => nat

Return the voting power of a given contract. The voting power value is the full staking power of the delegate, currently expressed in mutez. Though, developers should not rely on Tezos.voting_power to query the staking power of a contract in mutez: the value returned by Tezos.voting_power is still of typenat and it should only be considered relative toTezos.total_voting_power`.

Sapling

Delphi protocol introduced the following sapling types (state and transaction) with N being an int singleton

type st = 8 sapling_state
type tr = 8 sapling_transaction

type st = sapling_state<8>;
type tr = sapling_transaction<8>;

val sapling_empty_state : 'n sapling_state

let sapling_empty_state: sapling_state<n>

let x = Tezos.sapling_empty_state

let x = Tezos.sapling_empty_state ;

Sapling empty state

val sapling_verify_update : 'a sapling_transaction -> 'a sapling_state -> (bytes * (int * 'a sapling_state)) option

let sapling_verify_update: sapling_transaction<'a> => sapling_state<'a> => option<[bytes, [int, sapling_state<'a>]]>

Verify sapling update

let f (tr : tr) =
  match Tezos.sapling_verify_update tr x with
    Some (_, x) -> x
  | None -> (failwith "failed" : int * st)

let f = (tr : tr) =>
  match (Tezos.sapling_verify_update(tr, x)) {
    when(Some(p)): p[1];
    when(None()): failwith ("failed")
  };

Linearity

If a contract storage type contains a ticket, you must destructure the parameter-storage pair within the body to preserve storage linearity (e.g. avoid DUP-ing storage). For the same reasons, if tickets are stored in a map/big_map you must use the new operator get_and_update to update your bindings.

type storage = (string, int ticket) big_map
type parameter = int
type result = operation list * storage

[@entry]
let main (i : parameter) (store : storage) : result =
  let my_ticket1 = Option.unopt (Tezos.create_ticket i 10n) in
  let _, x = Big_map.get_and_update "hello" (Some my_ticket1) store
  in [], x

type storage = big_map<string, ticket<int>> ;

type parameter = int ;

type result = [list<operation>, storage];

@entry
function main (i: parameter, store : storage): result {
  let my_ticket1 = Option.unopt (Tezos.create_ticket (i, 10n));
  let [_x, ret] = Big_map.get_and_update ("hello", Some(my_ticket1), store);
  return [list([]), ret]
};

Timelock

val open_chest : chest_key -> chest -> nat -> bytes option

let open_chest : (key: chest_key, chest: chest, time: nat) => option<bytes>

Open a timelocked chest given its key and the time.