"Note that I am NOT suggesting that Unix is a state-of-the-art programming environment. There are many that are better, but this is the one we're using." M. Scott.

                                            Unix examples
    editors (structure?)                        vi, emacs ...
    pretty printers                             cb, indent ...
    pre-processors
        esp. macros                             cpp, m4, watfor ...
    debuggers (needs symbol table)              adb, sdb, dbx, gdb ...
    style checkers                              lint, purify, ...
    module management                           make
    version management                          sccs, rcs
    assemblers                                  as
    link editors, loaders                       ld, ld-so
    perusal tools                               more, less, od, nm ...
    program cross-referencing                   ctags
    
    The better, state-of-the-art environments have more integration to them.
    For example,
        Cedar, Smalltalk, Interlisp at Xerox PARC
        Common Lisp on Symbolics
        Sabre C on Unix
        MPW on Macs
        Visual Studio on PCs

    integration means
        if you get a syntax error message from the compiler your editor
            window pops up with the cursor at the mistake, for you to fix
        if your program gets a subscript error you pop up in the debugger
            without doing anything special
        the compiler has something like 'make' built in; it won't let you
            link together incompatible versions of things
        type checking works across separately-compiled modules
        the editor has automatic access to cross-referencing information
            on your program, so if you want to see all the places you call
            'foo' it's easy
        etc.