pyutil 1.9.7

a collection of utilities for Python programmers

current modules

These are useful! Use them.

• mathutil.py - integer power, floor, ceil, and nearest multiples; permute and fit slope
• memutil.py - statistics and diagnostics for memory use and garbage collection
• platformutil.py - get platform including Linux distro; more accurate and less noisy than platform.platform()
• strutil.py - common prefix and suffix of two strings, and newline processing
• assertutil.py - test preconditions, postconditions, and assertions
• benchutil.py - benchmark a function by running it repeatedly
• fileutil.py - work with files and directories
• iputil.py - query available local IPv4 addresses
• jsonutil.py - wrapper around simplejson which converts decimal inputs to Python Decimal objects instead of to Python floats
• lineutil.py - remove extra whitespace from files
• testutil.py - utilities for use in unit tests, especially in Twisted
• time_format.py - date and time formatting operations
• version_class.py - parse version strings into a Version Number object
• verlib.py - utility to compare version strings, by Tarek Ziade

current scripts

• passphrase - generate memorable random passphrases
• verinfo - print out versioning information about a Python package and/or module
• unsort - sort the lines of an input file into a random order
• try_decoding - try decoding some bytes with every codec and print the results
• lines - convert end-of-lines to the current system's native end-of-line format
• tailx - print all but the first K lines of a file

out of shape modules

I don't currently use these, but I still think they are possibly good ideas.

• nummedobj.py - number objects in order of creation for consistent debug output
• observer.py - the Observer pattern
• increasing.py - an implementation of a monotonically-increasing timer; By the way a future, better implementation of this would use CLOCK_MONOTONIC or CLOCK_MONOTONIC_RAW if it were available: http://stackoverflow.com/questions/1205722/how-do-i-get-monotonic-time-durations-in-python/1205762#1205762
• repeatable_random.py - Make the random and time modules deterministic, so that executions can be reproducible.
• cache.py - multiple implementations of a least-recently-used in-memory caching strategy, optimized for different sizes (note: I, Zooko, nowadays prefer a random-replacement cache eviction strategy over least-recently-used because the former has more consistent and predictable behavior)
• odict.py - ordered dictionary implementation: see PEP 372. Note: there is now (as of Python 2.7) an ordered dict implementation in the standard library, but I haven't checked if it is as good as this one.
• zlibutil.py - zlib decompression in limited memory

out of shape scripts

• time_comparisons - empirically look for timing attacks (incomplete)
• memdump2dot - generate graphviz file from memdump (probably incomplete)

deprecated modules

I no longer use these and I don't recommend that you do either.

• logutil.py - send log messages to Twisted logger if present, else Python library logger
• weakutil.py - allows a bound method's object to be GC'd
• twistedutil.py - callLater_weakly, a variant of Twisted's callLater which interacts more nicely with weakrefs
• PickleSaver.py - make all or part of an object persistent, by saving it to disk when it's garbage collected
• humanreadable.py - an improved version of the builtin repr() function
• hashexpand.py - cryptographically strong pseudo-random number generator based on SHA256
• find_exe.py - try different paths in search of an executable
• dictutil.py - several specialized dict extensions, as well as some convenient functions for working with dicts
• randutil.py - various ways to get random bytes
• xor.py - xor two same-length strings together

deprecated scripts

• randcookie - deprecated in favor of passphrase
• randfile - deprecated in favor of "head --bytes=$B /dev/urandom"

Thanks to Peter Westlake and Ravi Pinjala for help documenting what these do.