Map type

The type Map<K, V> is used to associate key values with data.

The following types can be used as key:

• unit type
• boolean type
• address type
• numeric types

The values can be of any type including other maps, structs, tuples or arrays.

Example:

contract Foo {
    bar: Map<address, Map<address, u256>>
    baz: Map<address, Map<u256, bool>>

    pub fn read_bar(self, a: address, b: address) -> u256 {
        return self.bar[a][b]
    }

    pub fn write_bar(mut self, a: address, b: address, value: u256) {
        self.bar[a][b] = value
    }

    pub fn read_baz(self, a: address, b: u256) -> bool {
        return self.baz[a][b]
    }

    pub fn write_baz(mut self, a: address, b: u256, value: bool) {
        self.baz[a][b] = value
    }
}