Update aborted if trigger function fails?

Hi,

I just noticed this (odd?) behaviour, and it kind of
scares me.

For testing purposes, I put a deliberate syntax error;
this wouldn't happen in a real-life situation. But what
if the error gets triggered by something that happens
later on? say, if the trigger function uses a field
that later on gets dropped from the table -- something
that was working fine all of a sudden produces syntax
errors while executing the function

(I just verified, to see if the server would let me
drop a column that is being referenced by a function
invoked by an active trigger, and it did let me drop
it).

Isn't this a little fragile? Is there something I
could do to avoid this situation? Should trigger
functions be extremely simple as to guarantee that
an error would never happen?

Thanks,

Carlos
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