CheckValues

class plasmapy.utils.decorators.checks.CheckValues(checks_on_return: Optional[Dict[str, bool]] = None, **checks: Dict[str, bool])

Bases: CheckBase

A decorator class to ‘check’ — limit/control — the values of input and return arguments to a function or method.

Parameters

• checks_on_return (Dict[str, bool]) – Specifications for value checks on the return of the function being wrapped. (see check values for valid specifications)

• **checks (Dict[str, Dict[str, bool]]) –

  Specifications for value checks on the input arguments of the function being wrapped. Each keyword argument in checks is the name of a function argument to be checked and the keyword value contains the value check specifications.

  The value check specifications are defined within a dictionary containing the keys defined below. If the dictionary is empty or omitting keys, then the default value will be assumed for the missing keys.

  Key	Type	Description
  can_be_negative	bool	[DEFAULT True] values can be negative
  can_be_complex	bool	[DEFAULT False] values can be complex numbers
  can_be_inf	bool	[DEFAULT True] values can be inf
  can_be_nan	bool	[DEFAULT True] values can be nan
  none_shall_pass	bool	[DEFAULT False] values can be a python None
  can_be_zero	bool	[DEFAULT True] values can be zero

Notes

• Checking of function arguments *args and **kwargs is not supported.

Examples

from plasmapy.utils.decorators.checks import CheckValues

@CheckValues(arg1={'can_be_negative': False, 'can_be_nan': False},
             arg2={'can_be_inf': False},
             checks_on_return={'none_shall_pass': True)
def foo(arg1, arg2):
    return None

# on a method
class Foo:
    @CheckValues(arg1={'can_be_negative': False, 'can_be_nan': False},
                 arg2={'can_be_inf': False},
                 checks_on_return={'none_shall_pass': True)
    def bar(self, arg1, arg2):
        return None

Attributes Summary

checks

Requested checks on the decorated function's input arguments and/or return.

Methods Summary

__call__(f)

Decorate a function.

Attributes Documentation

checks

Requested checks on the decorated function’s input arguments and/or return.

Methods Documentation

__call__(f)

Decorate a function.

Parameters

f – Function to be wrapped

Returns

wrapped function of f

Return type

function