Python hints

• yield and yield from

  This blog post gives a good introduction of how to use yield and yield from in Python.

• add local path with conda

  Similar to a normal IDE where a project root is required to import local modules, with emacs and lsp, I first need to include the path in the environment. To check current local paths, open a Python interpreter and use

    import sys
    for p in sys.path:
        print(p)
  

  To add a path with conda, use conda develop <path> inside the environment, note that redundant paths should be avoided, e.g., if both ~/src/ and ~/src/modulea are present in the paths, there could be a module resolvation issue. After adding the path, need to activate conda environment and ananconda mode in emacs. To remove a path, use conda develop --uninstall <path>.

• pdb

  pdb is a python debugger in emacs, to start pdb I first need to be in the buffer of the specific file, the keywords are similar to gdb: s goes into a function, n skips entering inner functions, b lists current breakpoints and b <line-number> set a breakpoint at the given line, c continues the execution until reaching a breakpoint. Sometimes, there is error in the python interpreter but works fine in pdb, restart the python interpreter process would likely solve the problem.