snip-copy 0.0.2

snips lines from text files (automate creation of student copy from solution)

snip_copy

snip_copy creates copies of a file, snipping away portions of the original.

Our motivating use-case is to allow instructors to manage only a rubric.py copy of their assignment which contains student instructions, solutions to all problems and, grading criteria to be shared with TAs. Using snip_copy one can quickly create solution.py and student.py versions of the same assignment from rubric.py.

Installation

pip install snip_copy

Quick-start

Consider an example input file input.txt:

this text will be left unmodified in all copies

#! snip-start: a, b
this text will be removed in copies a and b
#! snip-end

this text will (also) be left unmodified in all copies

Running snip_copy as:

    $ python3 -m snip_copy input.txt

generates two files, a.txt and b.txt where each has removed the snipped section.

Jupyter Notebooks

You can add snip commands to jupyter notebook cells (code or markdown) to achieve similar behavior as well. For example, given input rubric.ipynb, running the following command:

    $ python3 -m snip_copy.ipynb rubric.ipynb

generates solution.ipynb and student.ipynb.

Notes:

• a copy is made for each item which appears in a comma separated list after any snip-start command in the entire document
• snip commands are removed in all copies created
• Each snip command line contains #!, which comments out the line, so it may live unobtrusively in python code. You can modify this string to produce similar behavior in another programming language:

    $ python3 -m snip_copy input.txt --cmd '// !'

• It can be cumbersome to type the full names of every output file with every snip-start command. Consider using --split:

    $ python3 -m snip_copy hw_rub.txt --split '_'

which will "split" the input file name at the last occurrence of the given string. For example, if hw_rub.txt has the same contents as input.txt at the top, then the terminal command immediately above creates hw_a.txt and hw_b.txt.

• cells which do not include any snip commands are left unmodified in all copies
• if a cell's snip command would remove its entire contents, then we remove the cell entirely in the copy generated, rather than give a cell which is empty
• You can call snip_copy from within jupyter via a code containing:

>>> #! snip-start: stud, sol
>>> !python3 -m snip_copy hw_rub.ipynb`

which will make copies, removing this cell from each copy.