Arc Forum | Anyway, we must be able to access the global namespace too. If you overwrite = a...

Arc Forum

1 point by sacado 6119 days ago | link | parent

Anyway, we must be able to access the global namespace too. If you overwrite = and def, you can't. Or you have to define g= and gdef :)

4 points by almkglor 6119 days ago | link

Here's a different idea. Suppose that instead we build a basic modulesystem which transforms:

  (modules-base
     ;name of module.
     foo
     ;set of functions in this module
     (bar)
     ;set of module variables
     (nitz)
     ;set of functions from other modules
     ((module2 hmm niawniaw))
     (def bar (x) (hmm) (niawniaw) (do1 nitz (= nitz x))))

to:

  (= foo
     (with
        (bar nil nitz nil hmm module2!hmm niawniaw module2!niawniaw)
       (= bar (fn (x) (hmm) (niawniaw) (do1 nitz (= nitz x))))
       (fill-table (table) 'bar bar)))

Then we create another macro which simply scans through the code for (def ...) forms and transforms the following code:

   (module foo
     (use module2)
     (module-vars nitz)
     (def bar (x) (do1 nitz (= nitz x))))

to:

  (modules-base
     foo
     (bar)
     (nitz)
     ;gotten by taking (keys module2)
     ((module2 hmm niawniaw))
     (def bar (x) (do1 nitz (= nitz x))))

Weaknesses: (1) we can't make module-variables accessible outside. If we had access to environments, though, we could.

(2) macros are impossible as yet, whether shared or not. Possibly, we need macrolet, and adding some mechanism to store macros separately from the module table - possibly in a table-of-tables module-macros.

Implementation: simple scanning would be nice. However, modules-basic would be better implemented by a 'macrolet form.

Conclusion: We need macrolet.

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