Snipper
A lightweight framework for removing code from student solutions.
Installation
pip install codesnipper
What it does
This project address the following three challenges for administering a python-based course
- You need to maintain a (working) version for debugging as well as a version handed out to students (with code missing)
- You ideally want to make references in source code to course material "(see equation 2.1 in exercise 5)" but these tend to go out of date
- You want to include code snippets and code output in lectures notes/exercises/beamer slides
- You want to automatically create student solutions
This framework address these problems and allow you to maintain a single, working project repository.
The project is currently used in 02465 at DTU. An example of student code can be found at:
A set of lectures notes where all code examples/output are automatically generated from the working repository can be found a
- https://lab.compute.dtu.dk/tuhe/books (see Sequential decision making)
How it works
The basic functionality is quite simple. You start with your working script in your private repository and add special tags to the script.
In this case I have added the tags #!b
(cut a block) and #!f
(cut function scope).
def myfun(): #!f The error I am going to raise
""" The function docstring will not be removed"""
print("This is a function")
return 42
def a_long_function():
a = 234
print("a line")
print("a line") #!b
print("a line")
print("a line") #!b Insert three missing print statements.
print("a line")
return a
if __name__ == "__main__":
myfun()
This will produce the following file:
def myfun():
""" The function docstring will not be removed"""
# TODO: 2 lines missing.
raise NotImplementedError("The error I am going to raise")
def a_long_function():
a = 234
print("a line")
# TODO: 3 lines missing.
raise NotImplementedError("Insert three missing print statements.")
print("a line")
return a
if __name__ == "__main__":
myfun()
You can also use the framework to capture code snippets, outputs and interactive python output.
To do this, save the following in foo.py
def myfun(): #!s This snippet will be saved to foo.py in the output directory.
print("Hello") #!s
print("Do not capture me")
for i in range(4): #!o
print("Output", i)
print("Goodbuy world") #!o
print("don't capture me")
# Interactive pythong example
print("Hello World") #!i #!i # this is a single-line cutout.
These block-tags will create a file foo.py
(in the output directory) containing
def myfun():
print("Hello")
A file foo.txt
containing the captured output
Output 0
Output 1
Output 2
Output 3
Goodbuy world
and a typeset version of an interactive python session in foo.pyi
>>> print("hello world")
Hello World"
All these files can be directly imported into LaTeX
using e.g. minted
: You never need to mix LaTeX
code and python again!
Additional features:
- Include references using
\cite
and\ref
: This works by parsing yourLaTeX
.aux
files and automatically keep your references in code synchronized with your written material. See the 02465 students repository for examples: None of the references to the exercise material or lecture notes are hard-coded! - You can name tags using
#!s=bar
to get afoo_bar.py
snippet. This is useful when you need to cut multiple sessions. This also works for the other tags.