* Use g++'s type descriptor stuff.

* Garbage collection.

* Signal/exception handling should be re-written to use
  C++ exceptions.  But first g++ exception handling needs bettering.

* Interface to Interviews.

* Optimize sequence functions to avoid intermediate sequence.  (Streams).

FUNCTIONS NEEDED

* Transcendental functions.

* Remaining byte functions.

* Random number generation.

* Sorting.

* More pattern matching/scanning.

* Allow assignment to PWD (and not to OLDPWD).

* MAILCHECK etc.

* save VAR1:=EXPR1 VAR2:=EXPR2 => ACTION
  Save values of VARs; set then to values of EXPRs;
  evaluatate action.  On return (or failure), restore saved values.


