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### Problems With Python/Julia Syntax Mapping with dot ('.') Operator

*aka, why the annoying underscore syntax is needed*

Using PyCall, we can map python modules to Julia modules with the same syntax:

    python> import os
    python> os.uname()
    python> os.O_RDONLY

    julia> using PyCall
    julia> os = pywrap(pyimport("os"))
    julia> os.uname()
    julia> os.O_RDONLY

And using a recursive version of pywrap (`pyrecwrap`), we can get nested
modules to map also:

    python> import os
    python> os.path.genericpath.os.uname()

    julia> os = pyrecwrap(pyimport("os"))
    julia> os.path.genericpath.os.uname()

We can also map python classes to Julia modules:

    python> import pyx.style.linewidth as psl
    python> psl.THICK

    julia> ps = pywrap(pyimport("pyx.style"))
    julia> psl = pywrap(ps.linewidth)
    julia> psl.THICK

However, in Python a class/object can both have members and be called as an
initializer:

    python> psl.THIN
    python> psl(0.1)

But in Julia a Module can't act as a function.

Thus, a one-to-one syntax mapping just isn't going to work until (unless?) the
dot ('.') operator can be overridden (as of Julia 0.4 it may not).

The work around used in this project (PyX.jl) is to use underscores in
object/function names and dots in object/module names. Eg,
`style.linewidth(0.2)` vs. `style_linewidth.THICK`.