rlwrap or emacs

Of course you want to enjoy features like command line history, parenthesis matching and navigating through an expression with the arrow keys. Suppose you work on a Linux machine, you have two possibilities to get all these things. First you can install rlwrap. If you then invoke the interpreter with rlwrap ./cubint ..., the tool will catch all your input and you can replay it with the arrow keys. The second possibility is to use the editor emacs with sml-mode. If you set up emacs for SML, follow these steps:

• Load a file and switch to the SML mode (M-x sml-mode).
• Press CTRL-C + CTRL-B. Now you (hopefully) see an input prompt like "ML command: " in the mini-buffer.
• Input here the location of the compiled interpreter and press ENTER.
• Answer "Any Args: " with any of the arguments listed in section 2 and press ENTER.
• Now the content of the buffer is passed to the interpreter and you can go on working with it in the usual sml-mode fashion.

This approach also work with Emacs on Windows. Alternatively you can use the Windows XP shell that offers a command line history which also works in the interpreter. To input more complicated expressions use an arbitrary text editor and load the file with use "file" (cf. section 4).