Try/Cond

[Sean Hinde]

On Tuesday, October 21, 2003, at 08:05  pm, Richard Carlsson wrote:

>
> ----- Original Message -----
> From: "Sean Hinde" <sean.hinde@REDACTED>
> To: "Richard Carlsson" <richardc@REDACTED>
> Cc: "Erlang Questions" <erlang-questions@REDACTED>
> Sent: Tuesday, October 21, 2003 8:50 PM
> Subject: Re: Try/Cond
>
>
>> So try is like (guessing):
>>
>> try
>>   func1(xx),
>>   f2(yy)
>> catch
>>   {'EXIT', Reason} ->
>>     {error, oops};
>>   ok ->
>>     ok
>> end.
>>
>> ?
>
> The main points are 1) being able to definitely separate exceptions
> from return values, and 2) being able to catch only those exceptions
> one is interested in, letting everything else fall through. Something
> like:
>
>     try
>       f(X)
>     catch
>       {throw, file_not_found} ->
>           ...
>     end
>
> also, we want to be able to directly switch on the result in the
> successful case. Something like this:
>
>     try scan(FD) of
>       foo -> ...;
>       bar -> ...
>     catch
>       {throw, eof} ->
>           ...
>     end

So this is the same as:

case catch scan(Fd) of
	foo -> ...;
	bar -> ...;
	{throw, eof} ->
	 ....;
	Else -> exit(Else)
end.

or am I missing something more subtle?

Sean