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Property requires another Property

In this code, the fy code is used to define a property that requires another property in order to deliver its functionality. The property greeting uses another property, french_greeting, to provide its value. This approach allows for modular and reusable property definitions. Here’s how each part of the code is defined and how it works:

Syntax

property greeting: str using french_greeting:
    property french_greeting
mixins/property/greeting/using_french_greeting_fy.py
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"""fy
property greeting: str using french_greeting:
    property french_greeting
"""

import abc

from mixins.property.french_greeting.abc_fy import (
    FrenchGreeting_PropertyMixin_ABC,
)


# fy:start ===>>>
class Greeting_UsingFrenchGreeting_PropertyMixin(
    # Property Mixins
    FrenchGreeting_PropertyMixin_ABC,
    abc.ABC,
):
    @cached_property
    def _greeting(self) -> str:
        # fy:end <<<===
        return self._french_greeting

What we have accomplished here is that any method or property that requires property greeting is decoupled from french_greeting property. They do not need to know anything about french_greeting in order to deliver their own functionality that uses property greeting.

Breakdown of Syntax

  1. property greeting: str using french_greeting:
    • Property Declaration: Defines a property named greeting with a type of str (string).
    • Implementation Name: using french_greeting declares the name of the specific property implementation that is then referenced by the encapsulating flow when included in a flow.
  2. property french_greeting
    • Property Integration: Indicates that the greeting property depends on the french_greeting property. This means the value or behavior of greeting is derived from french_greeting.
  3. Code Generation:
    • Automatic Code Generation: The fy tool generates the code between # fy:start and # fy:end. This includes the class definition and the @property method annotation and declaration.
    • Base classes: FrenchGreeting_PropertyMixin_ABC base class ensures the french_greeting property is available. abc.ABC is required because FrenchGreeting_PropertyMixin_ABC is an abstract class.
  4. User Input:
    • The only code the user needs to write is the property definition within the """fy block.
    • After boilerplate code generation, the user can add custom functionality, such as return self._french_greeting to the property method body.