Builtin types

Boolean

phantom.boolean.*

Types describing objects that coerce to either True or False respectively when calling bool() on them.

  • Truthy

  • Falsy

Datetime

phantom.datetime.*

  • TZAware

  • TZNaive

Numeric intervals

phantom.interval.*

Types describing narrower sets of numbers than int and float.

Base classes

All the interval types subclass from Interval which provides the following class arguments.

  • check: IntervalCheck

  • low: float (defaults to negative infinity)

  • high: float (defaults to positive infinity)

Concrete subclasses must specify their runtime type bound as their first base. See corresponding predicate functions.

  • Interval

  • Open

  • Closed

  • OpenClosed

  • ClosedOpen

Concrete intervals

  • Natural, (0, ∞)

  • NegativeInt, (-∞, 0)

  • Portion, (0, 1)

Regular expressions

phantom.re.*

Takes pattern: Pattern[str] as class argument. See corresponding predicate functions.

  • Match, uses phantom.predicates.re.is_match.

  • FullMatch, uses phantom.predicates.re.is_full_match.

Sized collections

phantom.sized.*

Types describing collections with size boundaries. These types should only be used with immutable collections. There is a naive check that eliminates some of the most common mutable collections in the instance check, however a guaranteed check is probably impossible to implement, so some amount of developer discipline is required.

  • PhantomSized[T], takes class argument len: Predicate[float].

  • NonEmpty[T], a sized collection with at least one item.

  • Empty[T], an empty collection.

Sized types are created by subclassing PhantomSized and providing a predicate that will be called with the size of the tested collection. For instance, NonEmpty is implemented using len=numeric.greater(0).

← Getting Started Builtin predicates and factories →