Smart contract calls another smart contract's method with SmartPy

Question

How can I call a smart contract method from another smart contract with smartPy?

Use Case:

Lest's imagine that we have:

1. Smart contract with a function increment(a)
2. Smart contract with a function changeVarValue() that invokes the first Smart Contract's increment method.

Many thanks.

Answer 1

There is an example template here: https://smartpy.io/dev/index.html?template=collatz.py.

The documentation is here: http://smartpy.io/dev/reference.html#_contract_and_address.

Basically:

• define your target contract

• c = sp.contract(sp.TInt, address_of_the_target_contract, entry_point = "foo").open_some()

• use sp.transfer(-42, sp.mutez(0), c)