Enums, Records, and Collections

As with standard Python, FizzBee supports the standard sets, lists, and dictionaries. In addition to the standard sets and dictionaries where Python requires the types to be hashable, FizzBee also supports alternatives genericset and genericmap where the elements/keys can be non-hashable types.

Enums

To define an enum, Usually, these are defined at the top level.

Run in playground

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Color = enum('RED', 'YELLOW', 'GREEN')

action Init:
  color = Color.RED

action Next:
  if color == Color.RED:
    color = Color.GREEN
  elif color == Color.GREEN:
    color = Color.YELLOW
  else:
    color = Color.RED

To choose iterate over the enum values in for or any, you can simply use dir() builtin.

Run in playground

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Color = enum('RED', 'YELLOW', 'GREEN')

action Init:
  color = Color.RED

action Next:
  any c in dir(Color):
    color = c

enum in FizzBee is only a syntactic sugar over the standard string. So Color.RED == 'RED' is true. It is not a separate type, like Python’s enum.Enum.

Records

To define a record, These can be defined anywhere a standard python statement can be defined.

# Define a record
msg = record(node=5, color=Color.RED, message='Hello')

# Access the fields
msg.node
# Set the fields
msg.color = Color.GREEN

Immutable Struct

This may not be that useful, this comes with the Starlark language (that FizzBee is actually based on) so if needed use it.

msg = struct(node=5, color=Color.RED, message='Hello')

msg.node = 10 # This will throw an error

As an implementation detail, the enum feature is implemented as a struct with keys as the enum values.

Collections

List

Ordered list of elements. Common standard Python operations are supported. append,clear,extend,index,insert,pop,remove

list = [1, 2, 3]
list[0] = 4

Set

Unordered collection of unique elements. Common standard Python operations are supported. add,clear,difference,discard,intersection,issubset,issuperset,pop,remove,symmetric_difference,union


s = set([1, 2, 2])
# len(s) == 2
s.add(4)
# len(s) == 3
s.remove(2)
# len(s) == 2

Dictionary

Key-value pairs. Common standard Python operations are supported. clear,get,items,keys,pop,popitem,setdefault,update,values


d = {1: 'one', 2: 'two'}

d[1] = 'uno'

Generic Set

Unordered collection of unique elements. The elements can be non-hashable. The standard methods like add,clear,difference,discard,intersection,issubset,issuperset,pop,remove,symmetric_difference,union are supported, and looping over the elements is also supported


s = genericset()
s.add({'status': 'working', 'id': 1})
s.add({'status': 'pending', 'id': 2})
# len(s) == 2

# Adding the same element again does not change the size
s.add({'status': 'working', 'id': 1})
# len(s) == 2

Generic Map

Key-value pairs. The keys can be non-hashable. The standard methods like clear,get,items,keys,pop,popitem,setdefault,update,values are supported, and looping over the elements is also supported.


d = genericmap()
d[{'status': 'working', 'id': 1}] = 'one'
d[{'status': 'pending', 'id': 2}] = 'two'

Bag

A bag is a collection of elements where duplicates are allowed. The standard methods like add,add_all,clear,discard,pop,remove and looping over the elements are supported. Bag is also known as multiset.


b = bag()
b.add(1)
b.add(2)
b.add(2)
# len(b) == 3

print(b == bag([2, 1, 2])) # True Because, order of elements does not matter
print(b == bag([2, 1])) # False, because the number of '2' elements are different