Not too much, but already tests large parts of sensitive code. Caught a
bug where ,top would use (enter! #f) but enter grabbed the wrong
namespace since it was instantiated in the wrong namespace.
* Rename `make-command-{reader,evaluator}' -> `make-xrepl-{reader,evaluator}'
* Move the commented-out ,meta block to a better place
* Protect the prompt computation against errors, to avoid infinite
exception output if an exception is raised.
* Add ",switch ?" to query namespaces, and ",switch - <name>" to remove
one. Forbid resetting the default initial `*' namespace.
* Clarify that multiple arguments can be sent to ,stx and fix it to
display the current syntax when there are no arguments.
* Various minor typos and improvements.
* Restore the use-last-arguments-by-default functionality of ,rr
* Re-do argument reading to make it easier to have a default
argument (as in ,enter and ,edit).
requiring itself into the entered namespace.
This makes it useful in some cases where this require leads to a
dependency cycle, eg (enter! racket/list). It's obviously not useful
for use as-is, since you will not have a bound `enter!' to get out of
the namespace (and possibly no `require' to get it) -- but it is useful
for meta-tools like xrepl. This is why the flag is verbose. `xrepl'
now uses this flag.
Also, the check for valid keywords for the form is now done at runtime
rather than in the macro. This doesn't matter in this case, since the
form is intended for interactive use anyway.
Also, separate the two parts of `enter-load/use-compiled' (it was
defined curried, but didn't use it).
