fgen_runtime.base

Base class for wrapped derived types

INVALID_INSTANCE_INDEX

INVALID_INSTANCE_INDEX: int = -1

Value used to denote an invalid instance_index.

This can occur value when a wrapper class has not yet been initialised (connected to a Fortran instance).

FinalizableWrapperBase

class FinalizableWrapperBase(instance_index=-1)

Bases: ABC

Base class for model wrappers

abstract property exposed_attributes: tuple[str, ...]

Attributes exposed by this wrapper

abstract finalize()

Finalise the Fortran instance and set self back to being uninitialised

This method resets self.instance_index back to _UNINITIALISED_instance_index

Should be decorated with check_initialised()

Return type:

None

abstract classmethod from_new_connection()

Initialise by establishing a new connection with the Fortran module

This requests a new model index from the Fortran module and then initialises a class instance

Returns:

fgen_runtime.base.FinalizableWrapperBase – New class instance

property initialized: bool

Is the instance initialised, i.e. connected to a Fortran instance?

instance_index: int

Model index of wrapper Fortran instance

FinalizableWrapperBaseContext

class FinalizableWrapperBaseContext(model)

Bases: AbstractContextManager

Context manager for a wrapper

model: fgen_runtime.base.FinalizableWrapperBase

model instance to be managed

check_initialised

check_initialised(method)

Check that initialisation is called before execution

Parameters:

method (typing.TypeVar(FuncT, bound= typing.Callable[..., typing.Any])) – Method to wrap

Returns:

typing.TypeVar(FuncT, bound= typing.Callable[..., typing.Any]) – * Wrapped method. Before the method is called, initialisation will first be * checked. If the model wrapper hasn’t been initialised before the method is * called, an InitialisationError will be raised.

execute_finalize_on_fail

execute_finalize_on_fail(inst, func_to_try, *args, **kwargs)

Execute a function, finalising the instance before raising if any error occurs

This function is most useful in factory functions where it provides a clean way of ensuring that any Fortran is freed up in the event of an initialisation failure for any reason

Parameters:

• inst (fgen_runtime.base.FinalizableWrapperBase) – Instance whose model index we will use when executing the functin

• func_to_try (typing.Callable[[typing.Concatenate[int, typing.ParamSpec(P)]], typing.TypeVar(T)]) – Function to try executing, must take inst’s model index as its first argument

• *args (typing.ParamSpecArgs) – Passed to func_to_try

• **kwargs (typing.ParamSpecKwargs) – Passed to func_to_try

Returns:

typing.TypeVar(T) – Result of calling func_to_try(inst.instance_index, \*args, \*\*kwargs)

Raises:

Exception – Any exception which occurs when calling func_to_try. Before the     exception is raised, ``inst.finalize() is called.