Custom targets using patterns in Makefile - makefile

Question

I have a tree of files that looks like this:
.
├── Makefile
├── README.md
├── exercises
│   ├── 100-exercises.ipynb
│   ├── 200-exercises.ipynb
│   ├── 300-exercises.ipynb
│   └── 400-exercises.ipynb
├── notes
│   ├── 101-notes-pandas.ipynb
│   ├── 102-notes-matplotlib-1.ipynb
│   ├── 103-notes-numpy-scipy.ipynb
│   └── 104-notes-matplotlib-seaborn.ipynb
└── tasks
├── 101-tasks-pandas.ipynb
├── 102-tasks-matplotlib-1.ipynb
├── 103-tasks-numpy-scipy.ipynb
└── 104-tasks-matplotlib-seaborn.ipynb
I would like to add some targets that only operates on files according to patterns in their filename. For example:
make lecture-1
make lecture-1-notes
make lecture-1-exercises
make lecture-2
make notes
make exercises
...
etc.
where lecture-1 refers to the set of targets that have a filename beginning with a 1 e.g. tasks/101-tasks-pandas.ipynb - to be clear the patterns are:
notes -> ./notes/*
exercises -> ./exercises/*
tasks -> ./tasks/*
lecture-1 -> ./*/1[0-9][0-9]*.ipynb
lecture-2 -> ./*/2[0-9][0-9]*.ipynb
lecture-1-notes -> ./notes/1[0-9][0-9]*.ipynb
The long way would be to have a separate target for each but I feel like there must be some kind of pattern/regex matching that can be done to avoid this.
EDIT:
For more information on the operations done on each target, I have an executable command which basically converts the IPython notebook to HTML. This is stored as a variable in make called RENDER_HTML
e.g. At the moment to render everything in the notes folder I have the following sections in my Makefile:
RENDER_HTML=jupyter nbconvert --execute --to html
NOTES_TARGETS=$(wildcard ./notes/*.ipynb)
...
.PHONY: notes
notes: ${NOTES_TARGETS}
#mkdir -p $#/html/
${RENDER_HTML} $^
#mv $#/*.html $#/html/

Answer 1

It would be a lot easier for us to help you if you provided example of what kinds of rules you want and what they would do: maybe implementing rules for one of these by hand that can serve as an example.
Without having any idea what the targets and prerequisites are, what I suggest is that you use recursive make to compute a list of targets to build; something like this:
lecture-%:
$(MAKE) $(patsubst ???,???,$(wildcard */$(*)*))
I just used ??? here since you don't provide any information on how the source files are translated to targets: you'll have to do that part yourself :).
If you can define a rule that builds a single output file, like this:
notes/%:
#mkdir -p $(#D)/html/
${RENDER_HTML} $#.ipynb
#mv $(#D)/*.html $(#D)/html/
then you can do this:
lecture-%:
$(MAKE) $(patsubst %.ipynb,%,$(wildcard */$(*)*))
The mv command there confuses me somewhat (seems like there should be a better way to do that for sure) but it's what you have in your question so I guess it's right.
I'm suspicious that this won't work for you, depending on the answer to my question above. If the render command needs to see ALL the files (for example to build an index.html or something) then I don't quite understand how you want this to work, when it builds only some of the files. Basically, the problem is still under-specified to allow us to give a working solution. But maybe there's enough info here to get you started.