It is sometimes needed to access the worksheet path from the backend code. Specifically, I am trying to access the path information from Sage code: for example to include a separate script, or to write results to file. If the current path is not known, then absolute paths must be hardcoded in the worksheet, which might not be desirable as it is not a flexible solution. Reproducible: Always Steps to Reproduce: 1. Start Cantor and choose the Sage backend. 2. Type "import os; print __file__". 3. Save the worksheet. 4. Evaluate the current entry. Actual Results: An error is returned: NameError: name '__file__' is not defined Expected Results: It would be useful to obtain the path to the current worksheet. While this behaviour is completely normal, because the backend runs sage as an interactive server session which has no notion of "saved path", this limitation leads to hardcoding absolute paths into the current worksheet. A workaround would be to set the variable "__file__" when the worksheet is saved or loaded, so that it can be accessed with sage commands.
Created attachment 97006 [details] Allows to send the current worksheet path to backends on load/save. The patch introduces the "StoreWorksheetPath" backend capability. Backends with this capability state their interest in the current worksheet path. If a backend has this capability, the worksheets communicates its path to the session whenever it changes (on load/save). The backend can then act upon the change. The patch further implements this ability for the sage backend: when the path changes, it is stored into the "__file__" variable. This variable usually set by importing the "os" package. However, since sage is run in a server session, this variable is always unset within cantor.
What is the exact use case you need this for?
(In reply to Alexander Semke from comment #2) > What is the exact use case you need this for? My exact use case is a scientific application in C++, for which we require mathematical algorithms. These are prepared in cantor with sage backend. The resulting formulae are quite complicated, and we therefore use sage's codegen to generate C++ code (instead of manually translating the code). Once the code is generated, the C++ files are automatically updated by python/sage, thus skipping another manual step. Since the absolute location of the C++ files cannot be hardcoded in the sage script (as it changes when working on different machines), it has to be recalculated from the relative locations between the cantor worksheet and the C++ files. In the same spirit, anything that requires a file path is forced to use absolute paths. One example is including separate sage scripts from a personal library.
Git commit 976dbf7727389d022b8d884854ab2d3f8d008b50 by Alexander Semke. Committed on 30/04/2018 at 07:12. Pushed by asemke into branch 'master'. Make the path of the currently opened project file available in the sage session. FIXED-IN: 18.04.1 M +9 -0 src/backends/sage/sagesession.cpp M +1 -0 src/backends/sage/sagesession.h M +6 -0 src/lib/session.cpp M +10 -0 src/lib/session.h M +5 -1 src/worksheet.cpp https://commits.kde.org/cantor/976dbf7727389d022b8d884854ab2d3f8d008b50
Git commit 211c00896d3f64e3761832d3ab2e72cf28cbfc0d by Alexander Semke. Committed on 07/05/2018 at 20:45. Pushed by asemke into branch 'Applications/18.04'. Make the path of the currently opened project file available in the sage session. FIXED-IN: 18.04.1 M +9 -0 src/backends/sage/sagesession.cpp M +1 -0 src/backends/sage/sagesession.h M +6 -0 src/lib/session.cpp M +10 -0 src/lib/session.h M +5 -1 src/worksheet.cpp https://commits.kde.org/cantor/211c00896d3f64e3761832d3ab2e72cf28cbfc0d