Bits And Bobs

General utility functions with no dependencies.

Developer:

• Dan Saattrup Smart (dan.smart@alexandra.dk)

Installation

Install the package via uv or pip:

uv add bits_and_bobs

or

pip install bits_and_bobs

Overview of the utility functions

The package currently includes the following utility functions:

cache_arguments

An extension of the functools.cache/functools.lru_cache decorators, which can also cache specific arguments of a function, rather than always including all arguments. This is useful if you have a function with some arguments that do not affect the output, for instance a logging message or a verbosity flag.

Here is an example of how to use it:

>>> import bits_and_bobs as bnb
>>>
>>> @bnb.cache_arguments(["x", "y"])
>>> def add(x: int, y: int, logging_message: str = "Computing...") -> int:
... print(logging_message)
... return x + y
>>>
>>> # This will compute and cache the result
>>> print(add(1, 2))
Computing...
3
>>>
>>> # This will use the cached result, since x and y are the same
>>> print(add(1, 2, logging_message="This will not be printed"))
3

no_terminal_output

A context manager that suppresses all terminal output. This blocks all Python output, but also all output from underlying C/C++/Fortran libraries. This is useful if you want to silence noisy libraries, for instance in Terminal User Interfaces (TUIs).

Use it like this:

>>> import bits_and_bobs as bnb
>>>
>>> print("This will be printed")
This will be printed
>>>
>>> with bnb.no_terminal_output():
...  print("This will NOT be printed")
>>>
>>> # We can specify a condition that disables the suppression
>>> def print_if_debug():
...  with bnb.no_terminal_output(disable_condition=lambda: os.getenv("DEBUG") == "1"):
...   print("This will be printed only if DEBUG=1")
>>> print_if_debug()
>>> os.environ["DEBUG"] = "1"
>>> print_if_debug()
This will be printed only if DEBUG=1

only_allow_specific_loggers

This function restricts logging output to only the specified loggers, suppressing all others. This is useful if you care about log messages from only a few specific loggers and want to ignore the rest, usually coming from third-party libraries.

Here is an example of how to use it:

>>> import bits_and_bobs as bnb
>>> import logging
>>>
>>> logger1 = logging.getLogger("logger1")
>>> logger2 = logging.getLogger("logger2")
>>>
>>> bnb.only_allow_specific_loggers(["logger1"])
>>>
>>> logger1.warning("This will be printed")
WARNING:logger1:This will be printed
>>>
>>> logger2.warning("This will NOT be printed")

timeout

This context manager limits the execution time of a block of code. If the block exceeds the specified time limit, a TimeoutError is raised. This is useful for preventing long-running operations from hanging your program.

Here is an example of how to use it:

>>> import bits_and_bobs as bnb
>>> import time
>>> try:
...  with bnb.timeout(seconds=2):
...   time.sleep(3)  # This will take longer than 2 seconds
... except TimeoutError:
...  print("The operation timed out!")
The operation timed out!