On 2008 Aug 24, at 7:16, C.M.Brown wrote:
OK, so you're basically saying that segfaults can be eliminated with a strong type system, whereas pattern matching errors is the result of some
Not really, no. A sufficiently strong type system will eliminate segfaults (modulo bugs in the language runtime or erroneous use of the FFI); but Haskell arguably doesn't have a sufficiently strong type system: pattern match errors being the symptom, and the resolution is dependent types. That said, what I was really saying was that a pattern match error still gives you more information, and more easily, than a segfault: if it's not something trivial like dereferencing a null pointer, the segfault may well be in completely unrelated code because the erroneous operation (for example) overran a buffer and corrupted unrelated data. Whereas with laziness, you may have to do some footwork to find the actual error (ghci's debugger helps, as does hpc as someone else mentioned upthread) but it's deterministic. -- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH