If you really want to apply the catch-all to a variable assignment, you'll need to use the
'set' function to evaluate both arguments, e.g.:
However, this is a very odd statement, as variable assignment will rarely fail (unless perhaps you are attempting to assign a value to a protected symbol).
Instead, you would typically enclose the expression or group of expressions which are likely to throw an exception within the catch-all statement, for example, in your case this might appear something like:
This expression catches all exceptions thrown by the
vlax-curve-getParamAtPoint,
vlax-curve-getFirstDeriv,
angle, and
rtd functions. You would then test whether the value assigned to the symbol
'angg1' is an error object using
vl-catch-all-error-p.
However, in my opinion, I would always advise to avoid this form of programming unless absolutely necessary, as it can hide genuine errors in the logic of the program which should be handled gracefully prior to evaluating a function which would otherwise throw an exception for the given argument.
For this particular case, I would suggest narrowing down the reason for why your program is returning an error whilst evaluating these particular expressions, and the circumstances which give rise to such an error and then including code to gracefully account for it.