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> guile> (eq? (string->symbol "-i") '-i) > #f > Is this expected behavior for an R4RS scheme which supports complex > number? Yes. Not only expected, but required. The Subject line is of course misleading. There is nothing the matter with eq?. The issue is the Scheme reader - how should '-i be interpreted? It is clear from R4RS that -i is a number, and hence cannot be eq? to any symbol. > If so, it's a real pain in the ass for command line > processing... How so? Why would you use symbols for command line arguments? That seems completely inappropriate: - Symbol are case-insensitive (in standard Scheme, at least). - Many characters cannot be part of symbols, unless you quote them (which is non-standard), or use string->symbol. - Symbols are atomic, and so you cannot process individual characters (without using symbol->string). - Scheme uses strings for filenames, not symbols. - Symbols are interned, whihc is probably not appropriate to transient commmand-line arguments. A command-line argument-list is a sequence (list or vector) of strings, not symbols. If you want to be able to write '-i instead of "-i", well, I'm sorry, that is not Scheme. If you want a nice terse shell syntax for interactive commands, while still maintaining the power and semantics of Scheme, that is a reasonable goal, which I am happy to discuss. However, don't use the Scheme reader for that. For some of my ideas for a functional shell, see: http://www.cygnus.com/~bothner/Qshell.html --Per Bothner Cygnus Solutions bothner@cygnus.com http://www.cygnus.com/~bothner