Re: [Haskell-cafe] MonadError vs Control.Exception
On 6/05/2012, at 8:09 AM, Albert Y. C. Lai wrote: Exceptions appeared as early as in ML and Ada in the 1980s, Oh they go back long before that. PL/I had them in the 1960s (manual 1965, compiler 1966) and Burroughs Extended Algol for the B6700 had them in the 1970s (maybe already in 1969 when the B6500 was released). CLU had them in the late 70s. The exception handling in CLU paper is 1979 and says In referring to the condition as exceptions rather than errors we are following Goodenough. The term exception is chosen because, unlike the term error, it does not imply that anything is wrong; The 'jumpout' function in Pop2 was basically an early adoption of the idea of continuations via Landin's J-functions; it was used as an exception handling mechanism and that was in the early 70s. Exceptions first appeared under another name in the paper of David Parnas and Harald Würges response to undesired events in software systems in ICSE 1976. Since several programming languages offered exception handling of one sort or another well before that, that *cannot* be the first appearance of exceptions. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] MonadError vs Control.Exception
On 7/05/2012, at 10:17 AM, Richard O'Keefe wrote: The 'jumpout' function in Pop2 was basically an early adoption of the idea of continuations via Landin's J-functions; it was used as an exception handling mechanism and that was in the early 70s. Correction: apparently that should read 'in 1968'. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] MonadError vs Control.Exception
On 12-05-04 07:03 PM, Станислав Черничкин wrote: Hi, guys, I'm interested in best practices in using of each approach. Personally I like MonadError because it is more explicit and Control.Exception-s becomes really ugly in complex scenarios. [...] User has to deal with both, but have no evidence on none of them from type signatures or documentation. My opinion is largely recorded in my sarcastic http://www.vex.net/~trebla/haskell/exception.xhtml Be sure to click the click me if you can button and read again. My sarcastic article focuses on control flow and doesn't comment on types. I agree about seeing exception possibilities in types. But that was done 8 years ago: http://www.haskell.org/pipermail/haskell/2004-June/014271.html So, I hate exceptions, I blame it, I think exceptions is junk came from OO-world and horrible languages like C# or even more horrible like Java, and it should be wiped out from Haskell with fire. But it is only my humble opinion. While you are entitled to have opinions, and I am fine with those parts about I hate exceptions, exceptions is junk, it is irresponsible and unreasonable to use that right on objective, verifiable, historical facts. Yes, I really hate it when people do that. I think Oleg is from Vulcus without even asking anyone. I think everyone uses Java without hard data. Programmers' habit of subsituting thinking for empirical facts is one of many reasons why the software profession has not yet earned the engineering status. The only two responsible, reasonable positions are: 1. find the answer or 2. hold the position that you just don't know Exceptions appeared as early as in ML and Ada in the 1980s, before many people knew OO, before ML or Ada got OO stuff, before Java or C# existed (or when Java was an internal project under two old names at Sun), even before C++ got exceptions. Exceptions first appeared under another name in the paper of David Parnas and Harald Würges response to undesired events in software systems in ICSE 1976. Exceptions did not come from OO or languages you mentioned, and this is not about opinion. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] MonadError vs Control.Exception
Hi, guys, I'm interested in best practices in using of each approach. Personally I like MonadError because it is more explicit and Control.Exception-s becomes really ugly in complex scenarios. Here an example to illustrate my idea: http://hackage.haskell.org/packages/archive/network-conduit/0.4.0/doc/html/src/Data-Conduit-Network.html#bindPort. All network-conduit functions can raise IOException because of Socket-related stuff (and actually entire network-conduit is written to deal with IOException correctry) + Bind-port can raise ErrorCall (came from error bindPort: addrs is empty). User has to deal with both, but have no evidence on none of them from type signatures or documentation. Moreover, ErrorCall in this case can be caused by IOException (we try to bind only available address, we get IOException exception, we have no more address to try and raise ErrorCall), and I really don’t understand, why it should be treated in a different way. So, I hate exceptions, I blame it, I think exceptions is junk came from OO-world and horrible languages like C# or even more horrible like Java, and it should be wiped out from Haskell with fire. But it is only my humble opinion. Reality shows that Haskell provides extensive support for exceptions, it included in base libraries and everyone uses it, but MonadError is modest part of mtl, and don’t even have “bracket” and other useful functions. That is why I’m really interested in any your ideas and experience on using these approaches. Cheers, Stasik. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
