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Fexl – Highly robust functional evaluation

by fexl on 8/4/14, 8:04 PM with 3 comments

• by fexl on 8/4/14, 8:04 PM

  This version handles syntax errors, out of memory errors, and out of time errors, propagating them upward instead of halting with an error message, and reporting them in an orderly fashion at the end of the main program. Now the only calls to "die" are those which should never happen, i.e. they are pure assertions which are never expected to fail.

  This allows for some very nice embedded calls to parsing and evaluation from within a Fexl program itself, which can always be expected to return to the caller instead of halting.

  Ultimately I'm going to put a full-powered interpreter right on the web to allow arbitrary programs submitted from strangers, and this release is a necessary prerequisite for that.