Time for a ChangeLog!

1.34-SNAPSHOT

• Examples are now done by gigasquid

1.33

• Better windows anaconda support thanks to orolle.

• Moved to PyGILState* functions for GIL management. This mainly due to FongHou in PRs here and here.

• BREAKING CHANGE require-python now respects prefix lists -- unfortunately, the previous syntax was incorrect.

  ;; WRONG (syntax version < 1.33)
  (require-python '(os math)) 
  

  would be equivalent to

  ;; (do (require-python 'os) (require-python 'math))
  

  the correct syntax for this SHOULD have been

  (require-python 'os 'math)
  

  1.33 fixes this mistake, and provides support for prefix lists, for example:

  (require-python 
   '[builtins :as python]
   '(builtins 
     [list :as python.list]
     [dict :as python.dict]
     [tuple :as python.tuple]
     [set :as python.set]
     [frozenset :as python.frozenset]))
  

  (Note: this is done for you by the function libpython-clj.require/import-python)

  This fix brought to you by jjtolten.

1.32

• DecRef now happens cooperatively in python thread. We used to use separate threads in order to do decrement the refcount on objects that aren't reachable any more. Now it happens at the end of the with-gil macro and thus it is possible to have all python access confined to a single thread if this is desired for stability. It is also quite a bit faster as the GIL is captured once and all decrefs happen after that.

• Major performance and stability enhancements.

  1. Doubled down on single-interpreter design. This simplified some important aspects and led to a bit of perf gain.
  2. Implemented JNA DirectMapping for quite a few hotspots found via profiling some simple examples. Lots of people helped out with this (John Collins, Tom Poole (joinr)).

• Python executables can now be specified directly using the syntax

  (py/initialize! :python-executable <executable>)
  

  where executable can be a system installation of Python such as "python3", "python3.7"; it can also be a fully qualified path such as "/usr/bin/python3.7"; or any Python executable along your discoverable system path.

• Python virtual environments can now be used instead of system installations! This has been tested on Linux/Ubuntu variants with virtual environments installed with

  virtualenv -p $(which <python-version>) env
  

  and then invoked using

  (py/initialize! :python-executable "/abs/path/to/env/bin/python")
  

  Tested on Python 3.6.8 and Python 3.7.

  WARNING: This is suitable for casual hacking and exploratory development -- however, at this time, we still strongly recommend using Docker and a system installation of Python in production environments.

• breaking change (and remediation): require-python no longer automatically binds the Python module to the Clojure the namespace symbol. If you wish to bind the module to the namespace symbol, you need to use the :bind-ns flag. Example:

  (require-python 'requests) ;;=> nil
  requests ;;=> throws Exception
  
  (require-python '[requests :bind-ns]) ;;=> nil
  (py.. requests
        (get "https://www.google.com)
        -content
        (decode "latin-1)) ;; works
  

• Python method helper syntax for programmatic passing of maps to satisfy *args, **kwargs situations on the py. family of macros. Two new macros have been introduced to address this

  (py* obj method args)
  (py* obj method args kwargs)
  (py** obj method kwargs)
  (py** obj method arg1 arg2 arg3 ... argN kwargs)
  

  and the py.. syntax has been extended to accomodate these conventions as well.

  (py.. obj (*method args))
  (py.. obj (*method args kwargs))
  (py.. obj (**method kwargs))
  (py.. obj (**method arg1 arg2 arg3 ... argN kwargs))
  

Bugs Fixed:

• attribute calls with argument given in map
• allow specification of python executable
• difference in calling conventions leads to strange behavior in pandas with screencast of fix
• Allow single threaded use of Python
• Simplify interpreter design for only one interpreter

1.31

• Python objects are now datafy-able and nav-igable. require-python is now rebuilt using datafy.

• py., py.-, and py.. added to the libpython-clj APIs to allow method/attribute access more consistent with idiomatic Clojure forms.

1.30

This release is a big one. With finalizing require-python we have a clear way to use Python in daily use and make it look good in normal Clojure usage. There is a demo of facial recognition using some of the best open systems for doing this; this demo would absolutely not be possible without this library due to the extensive use of numpy and cython to implement the face detection. We can now interact with even very complex Python systems with roughly the same performance as a pure Python system.

Finalized require-python

Lots of work put in to make the require-python pathway work with classes and some serious refactoring overall.

Better Numpy Support

• Most of the datatype libraries math operators supported by numpy objects (+,-,etc).
• Numpy objects can be used in datatype library functions (like copy, make-container) and work in optimized ways.

libpython-clj.python.numpy-test> (def test-ary (py/$a np-mod array (->> (range 9)
                                                                        (partition 3)
                                                                        (mapv vec))))
#'libpython-clj.python.numpy-test/test-ary
libpython-clj.python.numpy-test> test-ary
[[0 1 2]
 [3 4 5]
 [6 7 8]]
libpython-clj.python.numpy-test> (dfn/+ test-ary 2)
[[ 2  3  4]
 [ 5  6  7]
 [ 8  9 10]]
libpython-clj.python.numpy-test> (dfn/> test-ary 4)
[[False False False]
 [False False  True]
 [ True  True  True]]

Bugs Fixed

• Support for java character <-> py string
• Fixed potential crash related to use of delay mechanism and stack based gc.
• Added logging to complain loudly if refcounts appear to be bad.

1.29

• Found/fixed issue with ->jvm and large Python dictionaries.

1.28

• (range 5) - Clojure ranges <-> Python ranges when possible.
• bridged types derive from collections.abc.* so that they pass instance checks in libraries that are checking for generic types.
• Really interesting unit test for generators, ranges and sequences.

1.27

• Fixed bug where (as-python {:is_train false}) results in a dictionary with a none value instead of a false value. This was found through hours of debugging why mxnet's forward function call was returning different values in Clojure than in Python.

1.26

• python startup work
• python generators & clojure transducers
• requre-python reload fix
• Bugfix with require-python :reload semantics.

1.25

Fixed (with tests) major issue with require-python.

1.24

Clojure's range is now respected in two different ways:

• (range) - bridges to a Python iterable
• (range 5) - copies to a Python list

1.23

Equals, hashcode, nice default .toString of Python types:

user> (require '[libpython-clj.python :as py])
nil
user> (def test-tuple (py/->py-tuple [1 2]))
#'user/test-tuple
user> (require '[libpython-clj.require :refer [require-python]])
nil
user> (require-python '[builtins :as bt])
nil
user> (bt/type test-tuple)
builtins.tuple
user> test-tuple
(1, 2)
user> (def new-tuple (py/->py-tuple [3 4]))
#'user/new-tuple
user> (= test-tuple new-tuple)
false
user> (= test-tuple (py/->py-tuple [1 2]))
true
user> (.hashCode test-tuple)
2130570162
user> (.hashCode (py/->py-tuple [1 2]))
2130570162
user> (require-python '[numpy :as np])
nil
user> (def np-ary (np/array [1 2 3]))
#'user/np-ary
user> np-ary
[1 2 3]
user> (bt/type np-ary)
numpy.ndarray
user> (py/python-type *1)
:type

1.22

Working to make more Python environments work out of the box. Currently have a testcase for conda working in a clean install of a docker container. There is now a new method: libpython-clj.python.interpreter/detect-startup-info that attempts call python3-config --prefix and python3 --version in order to automagically configure the Python library.

1.21

Bugfix release. Passing infinite sequences to Python functions was causing a hang as libpython-clj attempted to copy the sequence. The current calling convention does a shallow copy of things that are list-like or map-like, while bridging things that are iterable or don't fall into the above categories.

This exposed a bug that caused reference counting to be subtly wrong when Python iterated through a bridged object. And that was my life for a day.

1.20

With too many huge things we had to skip a few versions!

require-python

require-python works like require but it works on Python modules. require-python dynamically loads the module and exports it's symbols into a Clojure namespace. There are many options available for this pathway.

This implements a big step towards embedding Python in Clojure in a simple, clear, and easy to use way. One important thing to consider is the require has a :reload: option to allow you to actively develop a Python module and test it via Clojure.

This excellent work was in large part done by James Tolton.

• require-python-test

Clojure-defined Python classes

You can now extend a tuple of Python classes (or implement a new one). This system allows, among many things, us to use frameworks that use derivation as part of their public API. Please see classes-test for a documented example of a simple pathway through the new API. Note that if you use vanilla ->py-fn functions as part of the class definition you won't get access to the self object.

Bugfixes

A general stability bugfix was made that was involved in the interoperation of Clojure functions within Python. Clojure functions weren't currently adding a refcount to their return values.

1.16

Fixed a bug where the system would load multiple Python libraries, not stopping after the first valid library loaded. There are two ways to control the system's Python library loading mechanism:

1. Pass in a library name in initialize!
2. alter-var-root the list of libraries in libpython-clj.jna.base before calling initialize!.

1.15

Moar syntax sugar --

user> (py/$. numpy linspace)
<function linspace at 0x7fa6642766a8>
user> (py/$.. numpy random shuffle)
<built-in method shuffle of numpy.random.mtrand.RandomState object at 0x7fa66410cca8>

1.14

libpython-clj now searches for several shared libraries instead of being hardcoded to just one of them. Because of this, there is now:

libpython-clj.jna.base/*python-library-names*

This is a sequence of library names that will be tried in order.

You can also pass in the desired library name as part of the initialize! call and only this name will be tried.