pythonp 0.3.4

python -c with a handy print function p

What is pythonp?

pythonp is a simple utility script that helps you using python on the command line. Basically, it's a python -c command with a handy print function p. See examples below to see how convenient it can be.
By design, no magic is added in pythonp in a hope that it will be merged into some major python implementations later and becomes default setting for python -c. Therefore, any kind of valid python code should be able to run with pythonp and only python code can be run.

How to install

You can install it via pip

python -m pip install pythonp

or you can simply download this repository and copy __main__.py to one of your $PATH locations

cp pythonp/__main__.py ...../pythonp

Handy global variables defined

p

A handy print function with commandline usage in mind. It has the similar interface to the built-in print with some exceptions.

• It specially handles a single iterable as an argument, in which case it prints as many times as the number of elements in the iterable. Giving extra positional arguments along with an iterable is not allowed.

lines

Standard input lines. You can think of it as sys.stdin except that each line of it doesn't end with a newline character. Also note that it's subscriptable and allows a one-time random access, which means you can do something lines[3], lines[10:].

l

l is a line. It doesn't end with a new line character like each line of lines.
Without -e option, pythonp read a line from sys.stdlin and assign the line to l each time you access it. It's usually used to retrieve only the first few lines.
With -e option, it represent each line of the standard input. See the feature explanation about -e option below.

_lines

Lazy evaluted non-stream-like version of lines. Becuase it's a collections.abc.Sequence, you can access its lines multiple times, reverse it, do inclusion test on it, and so forth. The lines are not prepared until you actually use it to save up memory.

Features

• The last expression is automatically printed with p function if your code dind't write anything to sys.stdout and the last expression does not evalute to None. If you don't want this feature you can put something like ;pass or ;None in the end of your code.

• If -e option is given, your code can work on each line l, not the entire lines lines or _lines. The names lines and _lines will disappear and can not be used. Note that in the current implementation globals are shared among all lines and there could be side effects. This is a intended behavior but can change in the future.

• Automatic importing is supported. pythonp automatically tries to import a name for you when it encounters an unseen one.

• Backtick(`) in code is replaced with """ so that you can have one more way to make string literals. In python 3.6 or above f prefix is also added to make the enclosed section a f-string. For example, you can do something like

$ echo 91/seoul/bombs | pythonp -e "`name='{l.split('/')[2]}'`"  # python3.6+
name='bombs'

Examples

Print numbers

$ pythonp 'range(3)'
0
1
2

Print time

$ pythonp 'time.time()'
1546362172.5707405

Get the last item from a list

$ echo "1:2:3:4:5" | pythonp "l.split(':')[-1]"

List files whose names are longer than 5

$ ls | pythonp -e "if len(l)>5: p(l)"
LICENSE
README.md
pythonp
setup.py

Randomly sample N files to investigate from a large number of files

ls | pythonp "random.sample(_lines, 3)"
item_1443
item_6360
item_7285

Concatenate filenames

$ ls | pythonp "','.join(l.strip() for l in lines if not 'bombs' in l)"
LICENSE,README.md,pythonp,setup.py

Get the 4th column of the processs status

$ ps | tail -n+1 | pythonp -e "l.split()[3]"
/usr/local/bin/fish
-fish
python3
ssh

# or, using only pythonp
$ ps | pythonp "lines[1:]" | pythonp -e "l.split()[3]"

You can also do some crazy stuffs becuase pythonp can do anything that python can do

# If you have to solve a weird quiz
$ pythonp "now=datetime.datetime.now();(now.year+now.day)%10"

# Make at most 5 random names
$ pythonp "'\n'*5" | pythonp -e "''.join(random.sample(string.ascii_letters, 7))" | xargs touch

# If you want an one-liner crawler
$ cat urls.txt | pythonp -e 'requests.get(l.strip())' > output

Misc

• If you want a shorter name for pythonp you can do something like this.

mv $(which pythonp) $(dirname $(which pythonp))/p  # rename pythonp to p

• Both python2 and python3 are supported.

• Refer to python official docs to learn useful string manipulating functions https://docs.python.org/3/library/string.html

• It is a good idea to use generator expressions or list comprehensions with pythonp https://docs.python.org/3/howto/functional.html

• If you want some other features, you are always welcome to make an issue at the issue tab on the top menu.