On Thu, Feb 25, 2010 at 12:11 PM, Tobias C. Rittweiler <tcr@freebits.de> wrote:
a) "In function COS, value of argument is" -- Isn't there something
  missing in that part of the error message?

b) (length 12) does not give such an informative error message, just a
  boring "is not of type SEQUENCE"

What about the example below? I have created a function, FEwrong_type_nth_arg(), that outputs better error messages and register the calling function with a debugger frame, in case it was not already there. This way the message is nicer and the function appears in backtraces. I will commit it once I finish testing it.

> (cos 'a)

In function COS, the value of the first argument is
which is not of the expected type NUMBER

Available restarts:

1. (RESTART-TOPLEVEL) Go back to Top-Level REPL.

Broken at COS.
>> :v

Local variables: none
Special variables: none
>> :b

  > COS
  > si:bytecodes [Evaluation of: (cos 'a)]

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