class eosio::singleton

Class List > eosio :: singleton

Classes

Type Name
struct row

Public Functions

Type Name
singleton (name code, uint64_t scope)
bool exists ()
T get ()
Get the value stored inside the singleton table.
T get_or_default (const T & def = T())
T get_or_create (name bill_to_account, const T & def = T())
void set (const T & value, name bill_to_account)
void remove ()

Detailed Description

This wrapper uses a single table to store named objects various types.

Template parameters:

  • SingletonName - the name of this singleton variable
  • T - the type of the singleton

Public Functions Documentation

function singleton

eosio::singleton< SingletonName, T >::singleton(
    name code,
    uint64_t scope
)

Construct a new singleton object given the table's owner and the scope

Parameters:

  • code - The table's owner
  • scope - The scope of the table

function exists

bool eosio::singleton< SingletonName, T >::exists()

Check if the singleton table exists

Returns:

true - if exists

Returns:

false - otherwise

function get

T eosio::singleton< SingletonName, T >::get()

Get the value stored inside the singleton table.

Get the value stored inside the singleton table. Will throw an exception if it doesn't exist

Returns:

T - The value stored

function get_or_default

T eosio::singleton< SingletonName, T >::get_or_default(
    const T & def = T()
)

Get the value stored inside the singleton table. If it doesn't exist, it will return the specified default value

Parameters:

  • def - The default value to be returned in case the data doesn't exist

Returns:

T - The value stored

function get_or_create

T eosio::singleton< SingletonName, T >::get_or_create(
    name bill_to_account,
    const T & def = T()
)

Get the value stored inside the singleton table. If it doesn't exist, it will create a new one with the specified default value

Parameters:

  • bill_to_account - The account to bill for the newly created data if the data doesn't exist
  • def - The default value to be created in case the data doesn't exist

Returns:

T - The value stored

function set

void eosio::singleton< SingletonName, T >::set(
    const T & value,
    name bill_to_account
)

Set new value to the singleton table

Parameters:

  • value - New value to be set
  • bill_to_account - Account to pay for the new value

function remove

void eosio::singleton< SingletonName, T >::remove()

Remove the only data inside singleton table

The documentation for this class was generated from the following file: libraries/eosiolib/contracts/eosio/singleton.hpp