try
a <~ {ok, Result} = foo()
, b <~ {ok, R} = foo2()
catch
{a, Error_Code, Actual_Return_Value} -> ...
; {b, _} -> ...
end
Which essentially allows the same exact syntactic form you initially
disliked (a CRYPTIC operator), just with a different choice of what the
actual operator should be.
call it what you like.
it is not cryptic, because it has clarity.
and it ADDRESSES THE PROBLEM, not dancing around.
The problems with this form also include:
* you have to decide what happens if you specify a label that has no
match in the catch section?
what happens to any value that is not caught?
but it seems better to limit the labels scope to the single try,
and strip the labels from the return value of the try.
* you have to decide what happens if you specify a pattern that eats
up multiple labels in the catch section. Is this acceptable or it
breaks the spirit of the feature?
why not?
* can you guard on labels?
what?
* can labels be dynamically generated or are they compile-time constructs?
can try expressions be generated?
* the current syntax clashes with catching the result of throw({a,
ErrorCode, ReturnValue}), which means the syntax is too ambiguous to
serve its actual purpose without breaking backwards compatibility
the syntax is being DISCUSSED it is NOT CURRENT.
* the : operator is already used for fully qualified function calls,
same
DIXI.
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