Hi all, Georg Martius wrote:
I have some proposals for changes of the hierarchical module system as it is at the moment. [...] The hierarchical name can be derived from the place in the filesystem.
This is not a comment about the above proposal in itself, which arguably has its merits, but rather a meta comment. I get very anxious whenever I see "the file system" being mentioned in the context of a *language* specification (as opposed to, say, a specification of standard language libraries for interfacing with file systems). Some reasons: * File systems have all kinds of quirks one would rather not deal with in a language spec. * File systems can differ radically between different operating systems. In fact, even within an OS, as OS's these days tend to support many file systems simultaneously. * A valid module names in a language is not necessarily the same as a valid file name. (Yes, bijective mappings could be defined, but they would only be valid for a specific set of file systems.) * Even if we assume that the notion of a hierachical module name space always can be mapped to a corresponding file hierarchy in a simple way, why should that assumption be made in a language specification? In my opinion it is the task of the programming environment to locate the source files and interfaces that make up a semantically meaningful unit, and that semantics should be completely independent of where the different pieces happen to be stored. I'm already somewhat unhappy about the way most present Haskell tools map module names to path names (I'd generally prefer to have the possibility to flatten my file hierarchies by, say, using dots in my file names), but at least these assumptions are not in the Haskell 98 language definition. So, please, to the extent possible, let's keep the file system out of the Haskell' definition! All the best, /Henrik -- Henrik Nilsson School of Computer Science and Information Technology The University of Nottingham nhn@cs.nott.ac.uk This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.