LFE Documentation

LFE Shell (REPL)




        Lisp Flavoured Erlang (LFE) shell


        There is now a simple LFE shell in which you can enter sexprs
        which are evaluated and the value printed. There are no user
        shell variables (scoping and lack of setq)

        Built-in shell functions:

        (c File [Options])
            Compile and load an LFE file. Assumes default
            extension .lfe.

        (l Module ...)
            Load modules.

        (m Module ...)
            Print out module information, if no modules are given
            then print information about all modules.

        (ec File [Options])
            Compile and load an Erlang file.

        (slurp File)
            Slurp in a source LFE file and makes all functions and
            macros defined in the file available in the
            shell. Only one file can be slurped at a time and
            slurping a new file removes all data about the
            previous one.

            Remove all function and macro definitions except the
            default ones.

        (set Pattern Expr)
            Evaluate Expr ad match the result with Pattern binding
            variables in it. These variables can then be used in
            the shell and also rebound in another set.

        (: c Command Arg ...)
            All the commands in the standard Erlang shell can be
            reached in this way.

        Builtin shell variables:

            The three previous expressions input.
            The values of the previous 3 expressions.
            The current expression input.

    Starting the LFE shell

        The best way is probably to start Erlang directly running the
        LFE shell with:

        erl -noshell -noinput -s lfe_boot start

        This can easily be put in a shell script.

        From a normal Erlang shell the best way to start the shell is
        by calling:

        17> lfe_shell:server().

        Giving the user switch commands:

        --> s lfe_shell
        --> c

        will create a job running the LFE shell and connect to
        it. This also works when starting a remote shell.