#docopt

[mentalisttraceur-software]

My Markdown-with-frontmatter-YAML-to-Tumblr-NPF (and then `pytumblr2` to the Tumblr API) code is now wrapped in a very minimal CLI, and I have written Emacs glue for calling that CLI.

I am using `docopt`, which I reach for first when I need a Python CLI MVP, because it reduces boilerplate almost entirely down to just writing the `--help` text string.

(Naturally this post was created and updated through it. Basically ":w" to save changes in my text editor, two keys to switch from this file in my editor to my shell, then rerun the publish command from history to push updates. For the initial posting, I just had to tab-complete the file path and type out my blog name.)

Edit: I have now also added

CLI to get/set my two Tumblr-specific frontmatter fields,

Emacs code to prompt me interactively to pick from one of my blog names (I use Vertico+Orderless for `fzf`-like narrowing/search in all such prompts).

Emacs function to get the target Tumblr blog from the frontmatter (or prompt if it's not in there) and then call the publish CLI.

Emacs function to call the post deleting CLI.

Code within the above two functions to automatically reload the file from the file system if it had no unsaved changes before the publish/delete (to pick up the frontmatter change made by my Tumblr CLI, since that bypasses Emacs and edits the file itself).

(Naturally these latest edits were made by calling that function from within Emacs.)

Final edit: and now, finally, I can publish/update/delete posts with just three key presses (from vi command mode, when on the post's local Markdown file in my Emacs). Naturally, this final triumphant edit was published that way.

[stevenfusco]

neodoc - help text based nodejs command line parameter parsing

[ushf]

python argument parsing modules

A href="https://realpython.com/blog/python/comparing-python-command-line-parsing-libraries-argparse-docopt-click/">RealPython suggests that click is a very strong contender.

[fnielsen]

Docopt demonstration

For parsing command-line input argument in a script Python has the old argparse, optparse, and getopt modules. A new development is the docopt module that I have been using a bit for scripts related to Responsible Business Base.

The docopt module is a doctest-like approach where the command-line input specification is simply specified in the documentation (i.e., the docstring) of the script, just as you write the ordinary documentation. The simplicity in the approach may best be described by citing a YouTube comment: "holy shit".

Vladimir Keleshev has made his code available at https://github.com/docopt/docopt. It also installable via pip install docopt and http://docopt.org/ shows example.

Here is a small example which uses docopt in a program that fits a polynomium.

#!/usr/bin/env python """ mydocopter. Usage: mydocopter [options] <filename> Options: -v --verbose Log messages -o OUTPUT --output=OUTPUT Output file -a <a> Initial coefficient for second order term [default: 1.] -b <b> Initial coefficient for first order term [default: 1.] -c <c> Initial coefficient for constant term [default: 1.] Example: $ echo -e "1 4\\n2 5\\n6 8\\n3 3.2" > datafile.txt $ ./mydocopter --verbose datafile.txt 0.315471154631 -1.51271481921 5.64476836068 $ ./mydocopter -o p.txt datafile.txt $ ipython --pylab --c="m=loadtxt('datafile.txt'); p=loadtxt('p.txt'); x=linspace(1,6); plot(m[:,0], m[:,1], 'o', x, p[0]*x**2+p[1]*x+p[2], '-'); raw_input()" Description: Fit a polynomial to data. The datafile should have x y values in each row """ import docopt, logging, scipy.optimize args = docopt.docopt(__doc__, version=1.0) if args['--verbose']: logging.getLogger().setLevel(logging.INFO) a, b, c = (float(args['-' + coef]) for coef in ['a', 'b', 'c']) logging.info("Setting 'a' to %f" % a) logging.info('Reading data from ' + args['<filename>']) data = [ map(float, line.split()) for line in open(args['<filename>']).readlines()] def cost_function((a, b, c), data): return sum(map(lambda (x, y): (a*x**2 + b*x + c - y)**2, data)) parameters = scipy.optimize.fmin(cost_function, [a, b, c], args=(data,), disp=False) if args['--output'] is None: print(" ".join(map(str, parameters))) else: with open(args['--output'], 'w') as f: f.write(" ".join(map(str, parameters)))

[hongminhee]

doctest와 비슷한 아이디어인데, doctest도 그렇고 암시적인 것보다 명시적인 것을 선호하는 Python 철학에는 별로 좋은 아이디어로 여겨지지 않는 모양. 하여간 발상 자체는 참신한 것 같고, 간단한 스크립트 만들 때는 괜찮지 않을까 싶다.

이런 종류의 아이디어로는 Go 언어에서 쓰는 날짜 포매팅 방식도 있다. 예를 들어 strftime(3)으로는 %Y-%m-%d %H:%M:%S라고 써야 하는 것을 자연스럽게 2006-01-02 15:04:05라고 쓰면 그것으로부터 포맷을 뽑아내자는 아이디어. 그러니까, January, Jan, 01, 1 등은 무조건 월을 뜻하고, 15, 03, 3은 무조건 시간을 뜻하는 식.

[forvillelser]

docopt – pythonic option parser, that will make you smile

You know what's awesome? It's when the option parser is generated based on the help and usage-message that you write in a docstring!

"""

Usage: program.py [options] arguments

Options:

-h --help show this help message and exit

-v --verbose print status messages

-q --quiet report only file names

-r --repeat show all occurrences of the same error

--exclude=patterns exclude files or directories which match these comma separated patterns [default: .svn,CVS,.bzr,.hg,.git]

--filename=patterns when parsing directories, only check filenames matching these comma separated patterns [default: *.py]

--select=errors select errors and warnings (e.g. E,W6)

--ignore=errors skip errors and warnings (e.g. E4,W)

--show-source show source code for each error

"""

from docopt import docopt

def main(options, arguments):

   pass # ...

if __name__ == '__main__':

   # parse options based on docstring above

   options, arguments = docopt(__doc__)

   main(options, arguments)