With the Emacs shell, this goes a step further. Emacs functions and /bin/ commands are put in the same namespace. '+' is now a command that can be run at the command line, while 'grep' can have its output redirected to a buffer instead of a file (Sadly no input redirection). This, all while itself being a buffer.
It doesn't work well with full-screen programs, or ones that use escape sequences. Sadly there's no away around that besides keeping a list of those programs. Unix programs have never needed to say to the OS "I am a fullscreen program" due to how little a traditional shell actually interacts with a programs.
Emacs is my login shell now. I feel however that other, more pure attempts at this like the Canon Cat and Plan 9's text editor were smothered by the Mac/Windows interface of GUI programs which rarely interact. A more evolved shell never had the chance to arise.
It doesn't work well with full-screen programs, or ones that use escape sequences. Sadly there's no away around that besides keeping a list of those programs. Unix programs have never needed to say to the OS "I am a fullscreen program" due to how little a traditional shell actually interacts with a programs.
Emacs is my login shell now. I feel however that other, more pure attempts at this like the Canon Cat and Plan 9's text editor were smothered by the Mac/Windows interface of GUI programs which rarely interact. A more evolved shell never had the chance to arise.