In this post, I'll discuss how Leo can integrate with IPython and Jupyter notebooks so as to become a premier literate *computing *environment, as Offray uses the term.
This is a design document. I'll focus only on what the user sees and experiences, not on how Leo might actually get the job done.* tl:dr:* Read the summary. *IPython and Jupyter will remain essentially unchanged* I assume that both IPython and Jupyter will not change in their essential qualities. That is, IPython and Jupyter are *fixed* (constant). In particular, I assume that for the foreseeable future that Jupyter notebooks will be a *linear* list of cells, not a tree of cells. In any case, the following design would not change much if Jupyter notes ever *do* support trees of cells. *Implications* 1. As a direct consequence of this assumption, only Leo will explicitly deal with outlines. 2. There must be some way of converting (parts of) Leo outlines to a *list* of .ipynb files. There is considerable room for creativity in this conversion process. That is, we want to keep tree-to-notebooks process in the back of our mind as we think about Leo trees. *The Jupyter design* The jupyter notebook handles cells in a simple, intuitive manner as follows: 1. Running a code cell produces output *in that cell*. That is, the output is attached to the cell itself, not in a Qt popup window. 2. It's possible to switch the types of Jupyter cells from a dropdown menu. The cell types are Code, Markdown, Raw NB Convert and Heading. 3. There are Jupyter commands to run some or all cells, and to insert, delete and move cells. *A preliminary design* Imo, we probably want similar (or improved) behavior in Leo cells: - It should not be necessary to open a view-rendered window to see the output of a cell. - Cells should show the In and Out numbers, just like in IPython or Jupyter. - Leo directives will indicate the type of cells. Some of these directives will apply to descendant nodes. - Leo will provide commands to run all cells, selected cells, selected subtrees and marked cells. - Existing Leo commands will suffice to insert, delete, move, clone, promote and demote cells. *New directives* *@jupyter-notebook*: explicitly denotes a notebook. All descendants are IPython cells. Useful when converting a Leo outline to one or more Jupyter notebooks. *@cells*: All descendants are IPython cells. *@cell*: A single IPython cell. Within a cell, @language denotes the type of cell. @language markdown denotes a Jupyter Markdown cell. There probably is not great need for Jupyter Heading cells: they may come free with Leo's outline structure. @language python (or julia, or r, etc) denotes a code cell. *Behavior* There is lots of room for experimentation re behavior and rendering. In general, we want cells to work just like the corresponding Jupyter cells, but enhanced, when possible, by Leo's outline structure. For example, the rending of @markdown cells might include the rendering of all descendant @markdown cells, thereby making Jupyter Heading cells unnecessary with Leo itself. Otoh, Leo will "reconstitute" Heading cells when exporting @jupyter-notebook trees. *Summary* 1. New Leo directives will designate subtrees as containing IPython *cells*. Such cells will look and work like individual IPython cells. They will show In and Out numbers, and will show output directly, without the need for a viewrendered pane. 2. Leo's existing @language directives will indicate the type of cell. Such directives could affect which Jupyter kernel evaluates Code nodes. 3. Wherever possible, Jupyter commands and cells will be enhanced by Leo's outline structure. For example, the rendering of an @markdown tree may make Jupyter Heading cells unnecessary. 4. Converting an outline to one or more .ipynb files might allow easy cross-file references in the resulting Jupyter notebooks. A table-of-contents notebook would likely be easy to create. All comments welcome. Edward P. S. To prepare for this post, I have carefully read all the comments and references in the Leo + PlantUML workflow <https://groups.google.com/forum/#%21topic/leo-editor/hNkQG5n6X6M> thread. Naturally, I may have misunderstood something. Please correct me if so. EKR -- You received this message because you are subscribed to the Google Groups "leo-editor" group. To unsubscribe from this group and stop receiving emails from it, send an email to leo-editor+unsubscr...@googlegroups.com. To post to this group, send email to leo-editor@googlegroups.com. Visit this group at https://groups.google.com/group/leo-editor. For more options, visit https://groups.google.com/d/optout.
