function_declarations.md

Chapter 6: Function Declarations

A function declaration in Vyper looks like the following:

@external
def exampleFunction(name: String[64], age: uint256):
    pass

This is a function named exampleFunction that takes 2 parameters: a String[64] (name) and a uint256 (age).

Note that we're specifying the function visibility as external using the function decorator @external.

All functions must include one visibility decorator (@external or @internal). We will learn more about function visibility and decorators in the coming chapters.

You can define an empty function body using pass keyword. When it is executed, nothing happens.

Put it to the test

In our app, we're going to create some Pokemons. Let's create a function for that.

1. Create an external function named createPokemon. It should take three parameter:

• name (a String[32])
• dna (a uint256)
• HP (a uint256)

2. Use the pass keyword to define an empty function body.

** Template **

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** Solution **

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** Previous Chapter Solution **

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