chitin / TODO

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*   set local variables in config, have them appear in shell
*   getting the menu to NOT have leading quotes
*   remove/edit history
    -> important for removing passwords if accidentally typed
*   improve library usage of executables
*   interprocess communication
    -> sharing of variables between chitin processes
*   remove trailing whitespace from lines somehow. maybe as a final transformation when you hit enter?
*   `other_ls = method(:ls)` would be cool. note that ls is mapped to a binary and is not actually a method

*   menu doesn't erase itself sometimes
    -> cat and tabcomplete a file that is empty. output is correct but confusing

*   `pdflatex("full.tex") > NULLOUT` fails to produce the PDF,
    but `... > 'test'` works. weird.
*   ^C on running ruby programs kills the whole interpreter... womp.
*   slashes in filenames
*   `include Math; sin(5)` fails

*   Why do you have to do @line = '' in Coolline in order to not affect the
    history? History calls el.dup which creates a new object. It shouldn't
    matter if I do @line.clear on the original.

*   failures