type_enforced
Type Enforced
A pure python (no special compiler required) type enforcer for type annotations. Enforce types in python functions and methods.
Setup
Make sure you have Python 3.11.x (or higher) installed on your system. You can download it here.
- Unsupported python versions can be used, however newer features will not be available.
- For 3.7: use type_enforced==0.0.16 (only very basic type checking is supported)
- For 3.8: use type_enforced==0.0.16 (only very basic type checking is supported)
- For 3.9: use type_enforced<=1.9.0 (
staticmethod
, union with|
andfrom __future__ import annotations
typechecking are not supported) - For 3.10: use type_enforced<=1.10.2 (
from __future__ import annotations
may cause errors (EG: when using staticmethods and classmethods))
Installation
pip install type_enforced
Basic Usage
import type_enforced
@type_enforced.Enforcer(enabled=True, strict=True)
def my_fn(a: int , b: int | str =2, c: int =3) -> None:
pass
- Note:
enabled=True
by default if not specified. You can setenabled=False
to disable type checking for a specific function, method, or class. This is useful for a production vs debugging environment or for undecorating a single method in a larger wrapped class. - Note:
strict=True
by default if not specified. You can setstrict=False
to disable exceptions being raised when type checking fails. Instead, a warning will be printed to the console.
Getting Started
type_enforcer
contains a basic Enforcer
wrapper that can be used to enforce many basic python typing hints. Technical Docs Here.
Enforcer
can be used as a decorator for functions, methods, and classes. It will enforce the type hints on the function or method inputs and outputs. It takes in the following optional arguments:
enabled
(True): A boolean to enable or disable type checking. IfTrue
, type checking will be enforced. IfFalse
, type checking will be disabled.strict
(True): A boolean to enable or disable type mismatch exceptions. IfTrue
exceptions will be raised when type checking fails. IfFalse
, exceptions will not be raised but instead a warning will be printed to the console.
type_enforcer
currently supports many single and multi level python types. This includes class instances and classes themselves. For example, you can force an input to be an int
, a number int | float
, an instance of the self defined MyClass
, or a even a vector with list[int]
. Items like typing.List
, typing.Dict
, typing.Union
and typing.Optional
are supported.
You can pass union types to validate one of multiple types. For example, you could validate an input was an int or a float with int | float
or typing.Union[int, float]
.
Nesting is allowed as long as the nested items are iterables (e.g. typing.List
, dict
, ...). For example, you could validate that a list is a vector with list[int]
or possibly typing.List[int]
.
Variables without an annotation for type are not enforced.
Why use Type Enforced?
type_enforced
is a pure python type enforcer that does not require any special compiler or preprocessor to work.type_enforced
uses the standard python typing hints and enforces them at runtime.- This means that you can use it in any python environment (3.11+) without any special setup.
type_enforced
is designed to be lightweight and easy to use, making it a great choice for both small and large projects.type_enforced
supports complex (nested) typing hints, union types, and many of the standard python typing functions.type_enforced
is designed to be fast and efficient, with minimal overhead.type_enforced
offers the fastest performance for enforcing large objects of complex types- Note: See the benchmarks for more information on the performance of each type checker.
Supported Type Checking Features:
- Function/Method Input Typing
- Function/Method Return Typing
- Dataclass Typing
- All standard python types (
str
,list
,int
,dict
, ...) - Union types
- typing.Union
|
separated items (e.g.int | float
)
- Nested types (e.g.
dict[str, int]
orlist[int|float]
)- Note: Each parent level must be an iterable
- Specifically a variant of
list
,set
,tuple
ordict
- Specifically a variant of
- Note:
dict
requires two types to be specified (unions count as a single type)- The first type is the key type and the second type is the value type
- e.g.
dict[str, int|float]
ordict[int, float]
- Note:
list
andset
require a single type to be specified (unions count as a single type)- e.g.
list[int]
,set[str]
,list[float|str]
- e.g.
- Note:
tuple
Allows forN
types to be specified- Each item refers to the positional type of each item in the tuple
- Support for ellipsis (
...
) is supported if you only specify two types and the second is the ellipsis type- e.g.
tuple[int, ...]
ortuple[int|str, ...]
- e.g.
- Note: Unions between two tuples are not supported
- e.g.
tuple[int, str] | tuple[str, int]
will not work
- e.g.
- Deeply nested types are supported too:
dict[dict[int]]
list[set[str]]
- Note: Each parent level must be an iterable
- Many of the
typing
(package) functions and methods including:- Standard typing functions:
List
Set
Dict
Tuple
Union
Optional
Any
Sized
- Essentially creates a union of:
list
,tuple
,dict
,set
,str
,bytes
,bytearray
,memoryview
,range
- Note: Can not have a nested type
- Because this does not always meet the criteria for
Nested types
above
- Because this does not always meet the criteria for
- Essentially creates a union of:
Literal
- Only allow certain values to be passed. Operates slightly differently than other checks.
- e.g.
Literal['a', 'b']
will require any passed values that are equal (==
) to'a'
or'b'
.- This compares the value of the passed input and not the type of the passed input.
- Note: Multiple types can be passed in the same
Literal
as acceptable values.- e.g. Literal['a', 'b', 1, 2] will require any passed values that are equal (
==
) to'a'
,'b'
,1
or2
.
- e.g. Literal['a', 'b', 1, 2] will require any passed values that are equal (
- Note: If type is a
str | Literal['a', 'b']
- The check will validate that the type is a string or the value is equal to
'a'
or'b'
. - This means that an input of
'c'
will pass the check since it matches the string type, but an input of1
will fail.
- The check will validate that the type is a string or the value is equal to
- Note: If type is a
int | Literal['a', 'b']
- The check will validate that the type is an int or the value is equal to
'a'
or'b'
. - This means that an input of
'c'
will fail the check, but an input of1
will pass.
- The check will validate that the type is an int or the value is equal to
- Note: Literals stack when used with unions.
- e.g.
Literal['a', 'b'] | Literal[1, 2]
will require any passed values that are equal (==
) to'a'
,'b'
,1
or2
.
- e.g.
Callable
- Essentially creates a union of:
staticmethod
,classmethod
,types.FunctionType
,types.BuiltinFunctionType
,types.MethodType
,types.BuiltinMethodType
,types.GeneratorType
- Essentially creates a union of:
- Note: Other functions might have support, but there are not currently tests to validate them
- Feel free to create an issue (or better yet a PR) if you want to add tests/support
- Standard typing functions:
Constraint
validation.- This is a special type of validation that allows passed input to be validated.
- Standard and custom constraints are supported.
- This is useful for validating that a passed input is within a certain range or meets a certain criteria.
- Note: Constraints stack when used with unions.
- e.g.
int | Constraint(ge=0) | Constraint(le=5)
will require any passed values to be integers that are greater than or equal to0
and less than or equal to5
.
- e.g.
- Note: The constraint is checked after type checking occurs and operates independently of the type checking.
- This operates differently than other checks (like
Literal
) and is evaluated post type checking. - For example, if you have an annotation of
str | Constraint(ge=0)
, this will always raise an exception since if you pass a string, it will raise on the constraint check and if you pass an integer, it will raise on the type check.
- This operates differently than other checks (like
- Note: See the example below or technical constraint and generic constraint docs for more information. ```
- This is a special type of validation that allows passed input to be validated.
Interactive Example
>>> import type_enforced
>>> @type_enforced.Enforcer
... def my_fn(a: int , b: int|str =2, c: int =3) -> None:
... pass
...
>>> my_fn(a=1, b=2, c=3)
>>> my_fn(a=1, b='2', c=3)
>>> my_fn(a='a', b=2, c=3)
Traceback (most recent call last):
File "<python-input-2>", line 1, in <module>
my_fn(a='a', b=2, c=3)
~~~~~^^^^^^^^^^^^^^^^^
File "/app/type_enforced/enforcer.py", line 233, in __call__
self.__check_type__(assigned_vars.get(key), value, key)
~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/app/type_enforced/enforcer.py", line 266, in __check_type__
self.__exception__(
~~~~~~~~~~~~~~~~~~^
f"Type mismatch for typed variable `{key}`. Expected one of the following `{list(expected.keys())}` but got `{obj_type}` with value `{obj}` instead."
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "/app/type_enforced/enforcer.py", line 188, in __exception__
raise TypeError(f"TypeEnforced Exception ({self.__fn__.__qualname__}): {message}")
TypeError: TypeEnforced Exception (my_fn): Type mismatch for typed variable `a`. Expected one of the following `[<class 'int'>]` but got `<class 'str'>` with value `a` instead.
Nested Examples
import type_enforced
import typing
@type_enforced.Enforcer
def my_fn(
a: dict[str,dict[str, int|float]], # Note: For dicts, the key is the first type and the value is the second type
b: list[typing.Set[str]] # Could also just use set
) -> None:
return None
my_fn(a={'i':{'j':1}}, b=[{'x'}]) # Success
my_fn(a={'i':{'j':'k'}}, b=[{'x'}]) # Error =>
# TypeError: TypeEnforced Exception (my_fn): Type mismatch for typed variable `a['i']['j']`. Expected one of the following `[<class 'int'>, <class 'float'>]` but got `<class 'str'>` with value `k` instead.
Class and Method Use
Type enforcer can be applied to methods individually:
import type_enforced
class my_class:
@type_enforced.Enforcer
def my_fn(self, b:int):
pass
You can also enforce all typing for all methods in a class by decorating the class itself.
import type_enforced
@type_enforced.Enforcer
class my_class:
def my_fn(self, b:int):
pass
def my_other_fn(self, a: int, b: int | str):
pass
You can also enforce types on staticmethod
s and classmethod
s if you are using python >= 3.10
. If you are using a python version less than this, classmethod
s and staticmethod
s methods will not have their types enforced.
import type_enforced
@type_enforced.Enforcer
class my_class:
@classmethod
def my_fn(self, b:int):
pass
@staticmethod
def my_other_fn(a: int, b: int | str):
pass
Dataclasses are suported too.
import type_enforced
from dataclasses import dataclass
@type_enforced.Enforcer
@dataclass
class my_class:
foo: int
bar: str
You can skip enforcement if you add the argument enabled=False
in the Enforcer
call.
- This is useful for a production vs debugging environment.
- This is also useful for undecorating a single method in a larger wrapped class.
- Note: You can set
enabled=False
for an entire class or simply disable a specific method in a larger wrapped class. - Note: Method level wrapper
enabled
values take precedence over class level wrappers.
import type_enforced
@type_enforced.Enforcer
class my_class:
def my_fn(self, a: int) -> None:
pass
@type_enforced.Enforcer(enabled=False)
def my_other_fn(self, a: int) -> None:
pass
Validate with Constraints
Type enforcer can enforce constraints for passed variables. These constraints are validated after any type checks are made.
To enforce basic input values are integers greater than or equal to zero, you can use the Constraint class like so:
import type_enforced
from type_enforced.utils import Constraint
@type_enforced.Enforcer()
def positive_int_test(value: int |Constraint(ge=0)) -> bool:
return True
positive_int_test(1) # Passes
positive_int_test(-1) # Fails
positive_int_test(1.0) # Fails
To enforce a GenericConstraint:
import type_enforced
from type_enforced.utils import GenericConstraint
CustomConstraint = GenericConstraint(
{
'in_rgb': lambda x: x in ['red', 'green', 'blue'],
}
)
@type_enforced.Enforcer()
def rgb_test(value: str | CustomConstraint) -> bool:
return True
rgb_test('red') # Passes
rgb_test('yellow') # Fails
Validate class instances and classes
Type enforcer can enforce class instances and classes. There are a few caveats between the two.
To enforce a class instance, simply pass the class itself as a type hint:
import type_enforced
class Foo():
def __init__(self) -> None:
pass
@type_enforced.Enforcer
class my_class():
def __init__(self, object: Foo) -> None:
self.object = object
x=my_class(Foo()) # Works great!
y=my_class(Foo) # Fails!
Notice how an initialized class instance Foo()
must be passed for the enforcer to not raise an exception.
To enforce an uninitialized class object use typing.Type[classHere]
on the class to enforce inputs to be an uninitialized class:
import type_enforced
import typing
class Foo():
def __init__(self) -> None:
pass
@type_enforced.Enforcer
class my_class():
def __init__(self, object_class: typing.Type[Foo]) -> None:
self.object = object_class()
y=my_class(Foo) # Works great!
x=my_class(Foo()) # Fails
By default, type_enforced will check for subclasses of a class when validating types. This means that if you pass a subclass of the expected class, it will pass the type check.
Note: Uninitialized class objects that are passed are not checked for subclasses.
import type_enforced
class Foo:
pass
class Bar(Foo):
pass
class Baz:
pass
@type_enforced.Enforcer
def my_fn(custom_class: Foo):
pass
my_fn(Foo()) # Passes as expected
my_fn(Bar()) # Passes as expected
my_fn(Baz()) # Raises TypeError as expected
What changed in 2.0.0?
The main changes in version 2.0.0 revolve around migrating towards the standard python typing hint process and away from the original type_enfoced type hints (as type enforced was originally created before the |
operator was added to python).
- Support for python3.10 has been dropped.
- List based union types are no longer supported.
- For example
[int, float]
is no longer a supported type hint. - Use
int|float
ortyping.Union[int, float]
instead.
- For example
- Dict types now require two types to be specified.
- The first type is the key type and the second type is the value type.
- For example,
dict[str, int|float]
ordict[int, float]
are valid types.
- Tuple types now allow for
N
types to be specified.- Each item refers to the positional type of each item in the tuple.
- Support for ellipsis (
...
) is supported if you only specify two types and the second is the ellipsis type.- For example,
tuple[int, ...]
ortuple[int|str, ...]
are valid types.
- For example,
- Note: Unions between two tuples are not supported.
- For example,
tuple[int, str] | tuple[str, int]
will not work.
- For example,
- Constraints and Literals can now be stacked with unions.
- For example,
int | Constraint(ge=0) | Constraint(le=5)
will require any passed values to be integers that are greater than or equal to0
and less than or equal to5
. - For example,
Literal['a', 'b'] | Literal[1, 2]
will require any passed values that are equal (==
) to'a'
,'b'
,1
or2
.
- For example,
- Literals now evaluate during the same time as type checking and operate as OR checks.
- For example,
int | Literal['a', 'b']
will validate that the type is an int or the value is equal to'a'
or'b'
.
- For example,
- Constraints are still are evaluated after type checking and operate independently of the type checking.
Development
Running Tests, Prettifying Code, and Updating Docs
Make sure Docker is installed and running.
- Create a docker container and drop into a shell
./run.sh
- Run all tests (see ./utils/test.sh)
./run.sh test
- Prettify the code (see ./utils/prettify.sh)
./run.sh prettify
Update the docs (see ./utils/docs.sh)
./run.sh docs
Note: You can and should modify the
Dockerfile
to test different python versions.
1""" 2# Type Enforced 3[](https://badge.fury.io/py/type_enforced) 4[](https://opensource.org/licenses/MIT) 5[](https://pypi.org/project/type_enforced/) 6<!-- [](https://pypi.org/project/type_enforced/) --> 7 8A pure python (no special compiler required) type enforcer for type annotations. Enforce types in python functions and methods. 9 10# Setup 11 12Make sure you have Python 3.11.x (or higher) installed on your system. You can download it [here](https://www.python.org/downloads/). 13 14- Unsupported python versions can be used, however newer features will not be available. 15 - For 3.7: use type_enforced==0.0.16 (only very basic type checking is supported) 16 - For 3.8: use type_enforced==0.0.16 (only very basic type checking is supported) 17 - For 3.9: use type_enforced<=1.9.0 (`staticmethod`, union with `|` and `from __future__ import annotations` typechecking are not supported) 18 - For 3.10: use type_enforced<=1.10.2 (`from __future__ import annotations` may cause errors (EG: when using staticmethods and classmethods)) 19 20### Installation 21 22``` 23pip install type_enforced 24``` 25 26## Basic Usage 27```py 28import type_enforced 29 30@type_enforced.Enforcer(enabled=True, strict=True) 31def my_fn(a: int , b: int | str =2, c: int =3) -> None: 32 pass 33``` 34- Note: `enabled=True` by default if not specified. You can set `enabled=False` to disable type checking for a specific function, method, or class. This is useful for a production vs debugging environment or for undecorating a single method in a larger wrapped class. 35- Note: `strict=True` by default if not specified. You can set `strict=False` to disable exceptions being raised when type checking fails. Instead, a warning will be printed to the console. 36 37## Getting Started 38 39`type_enforcer` contains a basic `Enforcer` wrapper that can be used to enforce many basic python typing hints. [Technical Docs Here](https://connor-makowski.github.io/type_enforced/type_enforced/enforcer.html). 40 41`Enforcer` can be used as a decorator for functions, methods, and classes. It will enforce the type hints on the function or method inputs and outputs. It takes in the following optional arguments: 42 43- `enabled` (True): A boolean to enable or disable type checking. If `True`, type checking will be enforced. If `False`, type checking will be disabled. 44- `strict` (True): A boolean to enable or disable type mismatch exceptions. If `True` exceptions will be raised when type checking fails. If `False`, exceptions will not be raised but instead a warning will be printed to the console. 45 46`type_enforcer` currently supports many single and multi level python types. This includes class instances and classes themselves. For example, you can force an input to be an `int`, a number `int | float`, an instance of the self defined `MyClass`, or a even a vector with `list[int]`. Items like `typing.List`, `typing.Dict`, `typing.Union` and `typing.Optional` are supported. 47 48You can pass union types to validate one of multiple types. For example, you could validate an input was an int or a float with `int | float` or `typing.Union[int, float]`. 49 50Nesting is allowed as long as the nested items are iterables (e.g. `typing.List`, `dict`, ...). For example, you could validate that a list is a vector with `list[int]` or possibly `typing.List[int]`. 51 52Variables without an annotation for type are not enforced. 53 54## Why use Type Enforced? 55 56- `type_enforced` is a pure python type enforcer that does not require any special compiler or preprocessor to work. 57- `type_enforced` uses the standard python typing hints and enforces them at runtime. 58 - This means that you can use it in any python environment (3.11+) without any special setup. 59- `type_enforced` is designed to be lightweight and easy to use, making it a great choice for both small and large projects. 60- `type_enforced` supports complex (nested) typing hints, union types, and many of the standard python typing functions. 61- `type_enforced` is designed to be fast and efficient, with minimal overhead. 62- `type_enforced` offers the fastest performance for enforcing large objects of complex types 63 - Note: See the [benchmarks](https://github.com/connor-makowski/type_enforced/blob/main/benchmark.md) for more information on the performance of each type checker. 64 65## Supported Type Checking Features: 66 67- Function/Method Input Typing 68- Function/Method Return Typing 69- Dataclass Typing 70- All standard python types (`str`, `list`, `int`, `dict`, ...) 71- Union types 72 - typing.Union 73 - `|` separated items (e.g. `int | float`) 74- Nested types (e.g. `dict[str, int]` or `list[int|float]`) 75 - Note: Each parent level must be an iterable 76 - Specifically a variant of `list`, `set`, `tuple` or `dict` 77 - Note: `dict` requires two types to be specified (unions count as a single type) 78 - The first type is the key type and the second type is the value type 79 - e.g. `dict[str, int|float]` or `dict[int, float]` 80 - Note: `list` and `set` require a single type to be specified (unions count as a single type) 81 - e.g. `list[int]`, `set[str]`, `list[float|str]` 82 - Note: `tuple` Allows for `N` types to be specified 83 - Each item refers to the positional type of each item in the tuple 84 - Support for ellipsis (`...`) is supported if you only specify two types and the second is the ellipsis type 85 - e.g. `tuple[int, ...]` or `tuple[int|str, ...]` 86 - Note: Unions between two tuples are not supported 87 - e.g. `tuple[int, str] | tuple[str, int]` will not work 88 - Deeply nested types are supported too: 89 - `dict[dict[int]]` 90 - `list[set[str]]` 91- Many of the `typing` (package) functions and methods including: 92 - Standard typing functions: 93 - `List` 94 - `Set` 95 - `Dict` 96 - `Tuple` 97 - `Union` 98 - `Optional` 99 - `Any` 100 - `Sized` 101 - Essentially creates a union of: 102 - `list`, `tuple`, `dict`, `set`, `str`, `bytes`, `bytearray`, `memoryview`, `range` 103 - Note: Can not have a nested type 104 - Because this does not always meet the criteria for `Nested types` above 105 - `Literal` 106 - Only allow certain values to be passed. Operates slightly differently than other checks. 107 - e.g. `Literal['a', 'b']` will require any passed values that are equal (`==`) to `'a'` or `'b'`. 108 - This compares the value of the passed input and not the type of the passed input. 109 - Note: Multiple types can be passed in the same `Literal` as acceptable values. 110 - e.g. Literal['a', 'b', 1, 2] will require any passed values that are equal (`==`) to `'a'`, `'b'`, `1` or `2`. 111 - Note: If type is a `str | Literal['a', 'b']` 112 - The check will validate that the type is a string or the value is equal to `'a'` or `'b'`. 113 - This means that an input of `'c'` will pass the check since it matches the string type, but an input of `1` will fail. 114 - Note: If type is a `int | Literal['a', 'b']` 115 - The check will validate that the type is an int or the value is equal to `'a'` or `'b'`. 116 - This means that an input of `'c'` will fail the check, but an input of `1` will pass. 117 - Note: Literals stack when used with unions. 118 - e.g. `Literal['a', 'b'] | Literal[1, 2]` will require any passed values that are equal (`==`) to `'a'`, `'b'`, `1` or `2`. 119 - `Callable` 120 - Essentially creates a union of: 121 - `staticmethod`, `classmethod`, `types.FunctionType`, `types.BuiltinFunctionType`, `types.MethodType`, `types.BuiltinMethodType`, `types.GeneratorType` 122 - Note: Other functions might have support, but there are not currently tests to validate them 123 - Feel free to create an issue (or better yet a PR) if you want to add tests/support 124- `Constraint` validation. 125 - This is a special type of validation that allows passed input to be validated. 126 - Standard and custom constraints are supported. 127 - This is useful for validating that a passed input is within a certain range or meets a certain criteria. 128 - Note: Constraints stack when used with unions. 129 - e.g. `int | Constraint(ge=0) | Constraint(le=5)` will require any passed values to be integers that are greater than or equal to `0` and less than or equal to `5`. 130 - Note: The constraint is checked after type checking occurs and operates independently of the type checking. 131 - This operates differently than other checks (like `Literal`) and is evaluated post type checking. 132 - For example, if you have an annotation of `str | Constraint(ge=0)`, this will always raise an exception since if you pass a string, it will raise on the constraint check and if you pass an integer, it will raise on the type check. 133 - Note: See the example below or technical [constraint](https://connor-makowski.github.io/type_enforced/type_enforced/utils.html#Constraint) and [generic constraint](https://connor-makowski.github.io/type_enforced/type_enforced/utils.html#GenericConstraint) docs for more information. 134 ``` 135 136## Interactive Example 137 138```py 139>>> import type_enforced 140>>> @type_enforced.Enforcer 141... def my_fn(a: int , b: int|str =2, c: int =3) -> None: 142... pass 143... 144>>> my_fn(a=1, b=2, c=3) 145>>> my_fn(a=1, b='2', c=3) 146>>> my_fn(a='a', b=2, c=3) 147Traceback (most recent call last): 148 File "<python-input-2>", line 1, in <module> 149 my_fn(a='a', b=2, c=3) 150 ~~~~~^^^^^^^^^^^^^^^^^ 151 File "/app/type_enforced/enforcer.py", line 233, in __call__ 152 self.__check_type__(assigned_vars.get(key), value, key) 153 ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 154 File "/app/type_enforced/enforcer.py", line 266, in __check_type__ 155 self.__exception__( 156 ~~~~~~~~~~~~~~~~~~^ 157 f"Type mismatch for typed variable `{key}`. Expected one of the following `{list(expected.keys())}` but got `{obj_type}` with value `{obj}` instead." 158 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 159 ) 160 ^ 161 File "/app/type_enforced/enforcer.py", line 188, in __exception__ 162 raise TypeError(f"TypeEnforced Exception ({self.__fn__.__qualname__}): {message}") 163TypeError: TypeEnforced Exception (my_fn): Type mismatch for typed variable `a`. Expected one of the following `[<class 'int'>]` but got `<class 'str'>` with value `a` instead. 164``` 165 166## Nested Examples 167```py 168import type_enforced 169import typing 170 171@type_enforced.Enforcer 172def my_fn( 173 a: dict[str,dict[str, int|float]], # Note: For dicts, the key is the first type and the value is the second type 174 b: list[typing.Set[str]] # Could also just use set 175) -> None: 176 return None 177 178my_fn(a={'i':{'j':1}}, b=[{'x'}]) # Success 179 180my_fn(a={'i':{'j':'k'}}, b=[{'x'}]) # Error => 181# TypeError: TypeEnforced Exception (my_fn): Type mismatch for typed variable `a['i']['j']`. Expected one of the following `[<class 'int'>, <class 'float'>]` but got `<class 'str'>` with value `k` instead. 182``` 183 184## Class and Method Use 185 186Type enforcer can be applied to methods individually: 187 188```py 189import type_enforced 190 191class my_class: 192 @type_enforced.Enforcer 193 def my_fn(self, b:int): 194 pass 195``` 196 197You can also enforce all typing for all methods in a class by decorating the class itself. 198 199```py 200import type_enforced 201 202@type_enforced.Enforcer 203class my_class: 204 def my_fn(self, b:int): 205 pass 206 207 def my_other_fn(self, a: int, b: int | str): 208 pass 209``` 210 211You can also enforce types on `staticmethod`s and `classmethod`s if you are using `python >= 3.10`. If you are using a python version less than this, `classmethod`s and `staticmethod`s methods will not have their types enforced. 212 213```py 214import type_enforced 215 216@type_enforced.Enforcer 217class my_class: 218 @classmethod 219 def my_fn(self, b:int): 220 pass 221 222 @staticmethod 223 def my_other_fn(a: int, b: int | str): 224 pass 225``` 226 227Dataclasses are suported too. 228 229```py 230import type_enforced 231from dataclasses import dataclass 232 233@type_enforced.Enforcer 234@dataclass 235class my_class: 236 foo: int 237 bar: str 238``` 239 240You can skip enforcement if you add the argument `enabled=False` in the `Enforcer` call. 241- This is useful for a production vs debugging environment. 242- This is also useful for undecorating a single method in a larger wrapped class. 243- Note: You can set `enabled=False` for an entire class or simply disable a specific method in a larger wrapped class. 244- Note: Method level wrapper `enabled` values take precedence over class level wrappers. 245```py 246import type_enforced 247@type_enforced.Enforcer 248class my_class: 249 def my_fn(self, a: int) -> None: 250 pass 251 252 @type_enforced.Enforcer(enabled=False) 253 def my_other_fn(self, a: int) -> None: 254 pass 255``` 256 257## Validate with Constraints 258Type enforcer can enforce constraints for passed variables. These constraints are validated after any type checks are made. 259 260To enforce basic input values are integers greater than or equal to zero, you can use the [Constraint](https://connor-makowski.github.io/type_enforced/type_enforced/utils.html#Constraint) class like so: 261```py 262import type_enforced 263from type_enforced.utils import Constraint 264 265@type_enforced.Enforcer() 266def positive_int_test(value: int |Constraint(ge=0)) -> bool: 267 return True 268 269positive_int_test(1) # Passes 270positive_int_test(-1) # Fails 271positive_int_test(1.0) # Fails 272``` 273 274To enforce a [GenericConstraint](https://connor-makowski.github.io/type_enforced/type_enforced/utils.html#GenericConstraint): 275```py 276import type_enforced 277from type_enforced.utils import GenericConstraint 278 279CustomConstraint = GenericConstraint( 280 { 281 'in_rgb': lambda x: x in ['red', 'green', 'blue'], 282 } 283) 284 285@type_enforced.Enforcer() 286def rgb_test(value: str | CustomConstraint) -> bool: 287 return True 288 289rgb_test('red') # Passes 290rgb_test('yellow') # Fails 291``` 292 293 294 295## Validate class instances and classes 296 297Type enforcer can enforce class instances and classes. There are a few caveats between the two. 298 299To enforce a class instance, simply pass the class itself as a type hint: 300```py 301import type_enforced 302 303class Foo(): 304 def __init__(self) -> None: 305 pass 306 307@type_enforced.Enforcer 308class my_class(): 309 def __init__(self, object: Foo) -> None: 310 self.object = object 311 312x=my_class(Foo()) # Works great! 313y=my_class(Foo) # Fails! 314``` 315 316Notice how an initialized class instance `Foo()` must be passed for the enforcer to not raise an exception. 317 318To enforce an uninitialized class object use `typing.Type[classHere]` on the class to enforce inputs to be an uninitialized class: 319```py 320import type_enforced 321import typing 322 323class Foo(): 324 def __init__(self) -> None: 325 pass 326 327@type_enforced.Enforcer 328class my_class(): 329 def __init__(self, object_class: typing.Type[Foo]) -> None: 330 self.object = object_class() 331 332y=my_class(Foo) # Works great! 333x=my_class(Foo()) # Fails 334``` 335 336By default, type_enforced will check for subclasses of a class when validating types. This means that if you pass a subclass of the expected class, it will pass the type check. 337 338Note: Uninitialized class objects that are passed are not checked for subclasses. 339 340```py 341import type_enforced 342 343class Foo: 344 pass 345 346class Bar(Foo): 347 pass 348 349class Baz: 350 pass 351 352@type_enforced.Enforcer 353def my_fn(custom_class: Foo): 354 pass 355 356my_fn(Foo()) # Passes as expected 357my_fn(Bar()) # Passes as expected 358my_fn(Baz()) # Raises TypeError as expected 359``` 360 361## What changed in 2.0.0? 362The main changes in version 2.0.0 revolve around migrating towards the standard python typing hint process and away from the original type_enfoced type hints (as type enforced was originally created before the `|` operator was added to python). 363- Support for python3.10 has been dropped. 364- List based union types are no longer supported. 365 - For example `[int, float]` is no longer a supported type hint. 366 - Use `int|float` or `typing.Union[int, float]` instead. 367- Dict types now require two types to be specified. 368 - The first type is the key type and the second type is the value type. 369 - For example, `dict[str, int|float]` or `dict[int, float]` are valid types. 370- Tuple types now allow for `N` types to be specified. 371 - Each item refers to the positional type of each item in the tuple. 372 - Support for ellipsis (`...`) is supported if you only specify two types and the second is the ellipsis type. 373 - For example, `tuple[int, ...]` or `tuple[int|str, ...]` are valid types. 374 - Note: Unions between two tuples are not supported. 375 - For example, `tuple[int, str] | tuple[str, int]` will not work. 376- Constraints and Literals can now be stacked with unions. 377 - For example, `int | Constraint(ge=0) | Constraint(le=5)` will require any passed values to be integers that are greater than or equal to `0` and less than or equal to `5`. 378 - For example, `Literal['a', 'b'] | Literal[1, 2]` will require any passed values that are equal (`==`) to `'a'`, `'b'`, `1` or `2`. 379- Literals now evaluate during the same time as type checking and operate as OR checks. 380 - For example, `int | Literal['a', 'b']` will validate that the type is an int or the value is equal to `'a'` or `'b'`. 381- Constraints are still are evaluated after type checking and operate independently of the type checking. 382 383# Development 384## Running Tests, Prettifying Code, and Updating Docs 385 386Make sure Docker is installed and running. 387 388- Create a docker container and drop into a shell 389 - `./run.sh` 390- Run all tests (see ./utils/test.sh) 391 - `./run.sh test` 392- Prettify the code (see ./utils/prettify.sh) 393 - `./run.sh prettify` 394- Update the docs (see ./utils/docs.sh) 395 - `./run.sh docs` 396 397- Note: You can and should modify the `Dockerfile` to test different python versions.""" 398from .enforcer import Enforcer, FunctionMethodEnforcer