bpython - A fancy curses interface to the Python interactive interpreter
Pygments (apt-get install python-pygments)
A few people asked for stuff like syntax highlighting and autocomplete for the Python interactive interpreter. IPython seems to offer this (plus you can get readline behaviour in the vanilla interpreter) but I tried IPython a couple of times. Perhaps I didn't really get it, but I get the feeling that the ideas behind IPython are pretty different to bpython. I didn't want to create a whole development environment; I simply wanted to provide a couple of neat features that already exist and turn them into something a little more interactive.
The idea is to provide the user with all the features in-line, much like modern IDEs, but in a simple, lightweight package that can be run in a terminal window, so curses seemed like the best choice. Sorry if you use Windows.
bpython doesn't attempt to create anything new or groundbreaking, it simply brings together a few neat ideas and focuses on practicality and usefulness. For this reason, the "Rewind" function should be taken with a pinch of salt, but personally I have found it to be very useful. I use bpython now whenever I would normally use the vanilla interpreter, e.g. for testing out solutions to people's problems on IRC, quickly testing a method of doing something without creating a temporary file, etc..
I hope you find it useful and please feel free to submit any bugs/patches (yeah right)/suggestions to: firstname.lastname@example.org or place them at the bitbucket issue page for this project at: http://bitbucket.org/bobf/bpython/issues/
For any other ways of communicating with bpython users and devs you can find us at the communication page on the projects homepage: http://bpython-interpreter.org/community
Hope to see you there!
- In-line syntax highlighting.
This uses Pygments for lexing the code as you type, and colours appropriately. Pygments does a great job of doing all of the tricky stuff and really leaving me with very little to do except format the tokens in all my favourite colours.
- Readline-like autocomplete with suggestions displayed as you type.
Thanks to Python's readline interface to libreadline and a ready-made class for using a Python interpreter's scope as the dataset, the only work here was displaying the readline matches as you type in a separate curses window below/above the cursor.
- Expected parameter list.
As in a lot of modern IDEs, bpython will attempt to display a list of parameters for any function you call. The inspect module is tried first, which works with any Python function, and then pydoc if that fails, which seems to be pretty adequate, but obviously in some cases it's simply not possible. I used pyparsing to cure my nested parentheses woes; again, it was nice and easy.
I didn't call this "Undo" because I thought that would be misleading, but "Rewind" is probably as bad. The idea is that the code entered is kept in memory and when the Rewind function is called, the last line is popped and the entire code is re-evaluated. As you can imagine, this has a lot of potential problems, but for defining classes and functions, I've found it to be nothing but useful.
- Pastebin code/write to file.
I don't really use the save thing much, but the pastebin thing's great. Hit a key and what you see on the screen will be sent to a pastebin and a URL is returned for you to do what you like with. I've hardcoded paste.pocoo.org in for now, that needs to be fixed so it's configurable. Next release, I promise.
- Flush curses screen to stdout.
A featurette, perhaps, but I thought it was worth noting. I can't personally recall a curses app that does this, perhaps it's often not useful, but when you quit bpython, the screen data will be flushed to stdout, so it basically looks the same as if you had quit the vanilla interpreter.
See the sample-config file for a list of available options. You should save your config file as ~/.config/bpython/config (i.e $XDG_CONFIG_HOME/bpython/config) or specify at the command line:
bpython --config /path/to/bpython/config
For known bugs please see bpython's issue tracker at bitbucket:
CLI Windows Support
Obtain the less program from GnuUtils. This makes the pager work as intended. It can be obtained from cygwin or GnuWin32 or msys
Current version is tested with
- Curses 2.2
- pyreadline 1.7
- The curses used has a bug where the colours are displayed incorrectly:
- red is swapped with blue
- cyan is swapped with yellow
To correct this I have provided my windows.theme file.
This curses implementation has 16 colors (dark and light versions of the colours)