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How to get syntax highlighting for .enaml files in PyCharm?

I am trying to learn Enaml, which is an extension to the Python language that allows you to define hierarchical trees of objects used for graphical user interfaces.
Since enaml is a super-set of the Python language, its syntax can be different from Python's one and IDEs do not highlight it.
Is there any way to get enaml-syntax highlighting in PyCharm? Or maybe in some other IDE?
(I know that the package 'enaml-pygments' exists, but I have no idea how to make it work for automatic enaml-syntax highlighting in an IDE.)

I've added most of the keywords to this repo which you can import into PyCharm:

There are highlighters for a few editors in the Enaml repo. Maybe one of them can be used by PyCharm: https://github.com/nucleic/enaml/tree/master/tools

Today I found this settings menu that partially addresses the issue of adding any syntax to PyCharm:
https://blog.jetbrains.com/idea/2010/09/custom-file-types-in-intellij-idea/
Unfortunately it captures only the most simple features of a syntax.

I'm using Atom to work with Python/Enaml code. With the language-enaml package you get syntax highlighting plus some autoextension and docstring feature for Enaml (https://atom.io/packages/language-enaml). Add in git integration and packages like build-python to run you code from the editor and you have quite a nice IDE.

https://github.com/vahndi/pycharm-enaml-keywords
Open PyCharm
Go to File,
Import Settings...,
browse to the .jar file and click OK
Select All,
OK

change the priority of pythonpath

When I was loading certain modules [namely pygments.lexers Bash Lexer and pygments.formatters LatexFormatter] I was was getting an error that python couldn't find the modules. I then realised that this problem was being caused by my PYTHONPATH, which is set up for using paraview with python. It brings its own version of pygments, which doesn't work with nbconvert from the jupyter notebook for some reason [Note it is not totally disfunctional, as PythonLexer, and a few others were called without a problem, it was only the ones that I've mentioned above that couldn't be found].
I have a similar problem with mayavi, which wouldn't work with paraview's version of vtk.
Both of these problems can be resolved simply enough by commenting out the python path in the bashrc, but obviously then paraview won't work.
Is there any way to, for example, reduce the priority of the PYTHONPATH so that the system codes in /etc... are called preferentially, but paraview can still find the ones that it needs in the PYTHONPATH?
I am using python 2.76 on linux mint 17.3, paraview is version 4.4.0, installed from source code as per here

Ordering the entries in PYTHONPATH is partly right, but the system paths don't seem to get included until you run python, and then they get put at the end. So to put a system path in front, explicitly add it:
export PYTHONPATH="[path/to/system/files]:$PYTHONPATH"
It is kind of a hack, because the system path you add will be duplicated in sys.path. But it works.

Yes, you can import sys and manipulate sys.path as an ordinary list at runtime. You can rearrange what's there, or just insert at the beginning (sys.path.insert(0, 'path')). Do this before your import statement. If this will cause problems elsewhere, put it back after your import statement.
Note, this is fairly hacky. But it sounds like you might have a case for it, although I have not looked at these specific tools together.
Edit: this is more relevant if you want to control the python path at the level of individual imports within the course of one execution of python. If you want to control the path at the level of one full execution of Python, you can also set the python path on the command line for just that execution like this:
PYTHONPATH=/replacement/path/here python your_script.py
This is more verbose (unless you wrap it in a shell script or alias) than just calling python, but it lets you control the path one script at a time, wheres putting it into .bashrc/.bash_profile or similar changes it for your whole shell session.

export PYTHONPATH=$PYTHONPATH:<your_path> will give priority to system paths and only if something is not there will look on your path.
export PYTHONPATH=<your_path>:$PYTHONPATH will search <your_path> firstly and then $PYTHONPATH for what it does not find.
If something exists in both but you want to use one version of it for one program and the other for another then you might want to look on different bashrc profiles.

A list of useful Python commands for Vim?

I was looking for a quick way to autoformat/pretty-print JSON in Vim the other day and found this great little command on Stack Overflow: :%!python -m json.tool
That sent me on a search for a list of other Python tools to pretty-print common web files, but I couldn't find much. Is there a good resource/list of Python tools that they find particularly useful for cleaning up poorly formatted web stuff inside Vim (e.g. HTML, XML, JavaScript, etc.)?

Python
Are you just looking for a resource for Python one-liners? You could browse through the Python standard library documentation to find more inspiration.
Or simply google "python one-liners json.tool" to find additional resources. For example, this Reddit post: Suggestion for a Python blogger: figure out what what all the stdlib main functionality is, and document it
Command line
Vim supports more than just Python (e.g. HTML Tidy as Keith suggested). Any tool that can accept pipe/standard input will integrate well with Vim.
The % command just picks a range that contains the entire file, and ! filters that range through an external program.
See :help :% and :help :!

For XHTML and XML files you can use tidy.
:%!tidy -i -asxhtml -utf8
:`<,`>!tidy -i -xml -utf8
The last one works on visual selections.

Vim has a command to do it, = (equal), like in ggvG= will reindent the whole file. Try :help = for more info about how to use functions and external programs with =. The default configuration uses internal indenting rules which works for most file types.

There are loads of good tools that are can convert text between the two formats:
par: for hard line wrapping.
pandoc: for HTML, LaTeX, rst, and Markdown
autopep8: for parsing Python code into an AST and spitting it out as pep8 compliant.
...
Vim is designed to make use of such utilities by the powerful formatprg settings. That by default is mapped to the gq operator. It works well with Vim motions, Vim text objects, selections, etc.
For instance, I use the setting below for on my Python files
au FileType python setlocal formatprg=autopep8\ --indent-size\ 0\ -
John MacFarlne has a good article about creating a specialised script using pandoc which you could stick in your vimrc.

!autopep8 -i % seems to work fine in vim . The -i switch is to over-write the existing file in place. Use more # autopep8 --help.
There is a vim plugin for this if you really are thinking of being a power user. Outside of vim you can test it with autopep8 -diff {filename} or autopep8 {filename}.

Which Python IDE can run my script line-by-line?

I wouldn't call myself programmer, but I've started learning Python recently and really enjoy it.
I mainly use it for small tasks so far - scripting, text processing, KML generation and ArcGIS.
From my experience with R (working with excellent Notepad++ and NppToR combo) I usually try to work with my scripts line by line (or region by region) in order to understand what each step of my script is doing.. and to check results on the fly.
My question: is there and IDE (or editor?) for Windows that lets you evaluate single line of Python script?
I have seen quite a lot of discussion regarding IDEs in Python context.. but havent stubled upon this specific question so far.
Thanks for help!

If you like R's layout. I highly recommend trying out Spyder. If you are using windows, try out Python(x,y). It is a package with a few different editors and a lot of common extra modules like scipy and numpy.

The only one I've had success with is Eclipse with Pydev

It's not an IDE, but you can use pdb to debug and step through your Python code. I know Emacs has built in support for it, but not so much about other editors (or IDEs) that will run in Windows.

If you are on Windows, give Pyscripter a try -- it offers comprehensive, step-through debugging, which will let you examine the state of your variables at each step of your code.

PyCharm from JetBrains has a very nice debugger that you can step through code with.
Django and console integration built in.

Rodeo seems to be new contender on the IDE market and the docs indicate that running lines of code is possible. I also have to admit it looks and behaves pretty good so far!

WingIDE, I've been using it successfully for over a year, and very pleased with it.

I use Notepad++ for most of my Windows based Python development and for debugging I use Winpdb. It's a cross platform GUI based debugger. You can actually setup a keyboard shortcut in Notepad++ to launch the debugger on your current script:
To do this go to "Run" -> "Run ..." in the menu and enter the following, making sure the path points to your winpdb_.pyw file:
C:\python26\Scripts\winpdb_.pyw "$(FULL_CURRENT_PATH)"
Then choose "Save..." and pick a shortcut that you wish to use to launch the debugger.
PS: You can also setup a shortcut to execute your python scripts similarly using this string instead:
C:\python26\python.exe "$(FULL_CURRENT_PATH)"

The upcoming RStudio 1.2 is so good that you have to try to write some python with it. 🙌

I would plump for EMACS all round.
If you're looking for a function to run code line by line (or a region if you have one highlighted), try adding this to your .emacs (I'm using python.el and Pymacs):
;; send current line to *Python
(defun my-python-send-region (&optional beg end)
(interactive)
(let ((beg (cond (beg beg)
((region-active-p)
(region-beginning))
(t (line-beginning-position))))
(end (cond (end end)
((region-active-p)
(copy-marker (region-end)))
(t (line-end-position)))))
(python-shell-send-region beg end)))
(add-hook 'python-mode-hook
'(lambda()
(local-set-key [(shift return)] 'my-python-send-region)))
I've bound it to [shift-Return]. This is borrowed from here. There's a similar keybinding for running .R files line by line here. I find both handy.

I like vim-ipython. With it I can <ctrl>+s to run a specific line. Or several lines selected on visual modes. Take a look at this video demo.

Visual Studio and PTVS: http://www.hanselman.com/blog/OneOfMicrosoftsBestKeptSecretsPythonToolsForVisualStudioPTVS.aspx
(There is also a REPL inside VS)

The Pythonwin IDE has a built-in debugger at lets you step through your code, inspect variables, etc.
http://starship.python.net/crew/mhammond/win32/Downloads.html
http://sourceforge.net/projects/pywin32/
The package also includes a bunch of other utility classes and modules that are very useful when writing Python code for Windows (interfacing with COM, etc.).
It's also discussed in the O'Reilly book Python Programming On Win32 by Mark Hammond.

Take the hint: The basic Python Read-Execute-Print-Loop (REPL) must work.
Want Evidence?
Here it is: The IDE's don't offer much of an alternative. If REPL wasn't effective, there's be lots of very cool alternatives. Since REPL is so effective, there are few alternatives.
Note that languages like Java must have a step-by-step debugger because there's no REPL.
Here's the other hint.
If you design your code well, you can import your libraries of functions and classes and exercise them in REPL model. Many, many Python packages are documented by exercising the package at the REPL level and copying the interactions.
The Django documentation -- as one example -- has a lot of interactive sessions that demonstrate how the parts work together at the REPL prompt.
This isn't very GUI. There's little pointing and clicking. But it seems to be effective.

You need to set the keyboard shortcut for "run selection" in
Tools > Preferences > Keyboard shortcuts
Then, select the line and hit the "run selection" shortcut

Light Table was doing that for me, unfortunately it is discontinued:
INLINE EVALUTION No more printing to the console in order to view your
results. Simply evaluate your code and the results will be displayed
inline.

Howto ignore specific undefined variables in Pydev Eclipse

I'm writing a crossplatform python script on windows using Eclipse with the Pydev plugin. The script makes use of the os.symlink() and os.readlink() methods if the current platform isn't NT.
Since the os.symlink() and os.readlink() methods aren't available on the Windows platform Pydev flags them as undefined variables--like so:
Question:
Is there a way to ignore specific undefined variable name errors without modifying my source file?
edit: I found a way to ignore undefined variable errors from this answer on stackoverflow.
I'll leave the question open in case there is a way to solve this using project file or Pydev setting.

I use pydev + pylint.
With pylint you can add which messages to ignore in the Preferences>Pydev>Pylint>"Aggruments to pass to pylint" section.
--disable-msg=W0232,F0401
You can ignore messages in-line as well with comments:
os.symlink(target, symlink) # IGNORE:<MessageID>
Mouse-over the "x" where the line numbers are to see the message id.

I suspect pydev may have better, specific solutions, but what about just putting some code at the start of your program, such as:
if not hasattr(os, 'symlink'): os.symlink = None
Yeah, it's a hack, but, unless pydev does have specialized solutions (unfortunately I don't know of any, but then I'm no pydev expert;-), may be better than nothing...

I noticed PyDev doesn't recognize ZeroMQ constants so I struggled with the same problem.
I found PyDev has a settings option in Preferences > PyDev > Code Editor > Code Analysis : Undefined-tab. Just write symlink and readlink there (comma separated) to remove the errors.
Still not optimal, but good enough for now.