Maps

1. mut m := map[string]int{} // Only maps with string keys are allowed for now
2. m['one'] = 1
3. println(m['one']) // ==> "1"
4. println(m['bad_key']) // ==> "0"
5. // TODO: implement a way to check if the key exists

7. numbers := { // TODO: this syntax is not implemented yet
8. 'one': 1,
9. 'two': 2,
10. }