pyAttach
========
A convenience function to attach Python objects to R.    


Usage
-----
.. code-block:: R

    pyAttach(what, env = parent.frame())

Arguments
---------
.. raw:: html

    <table style="width:100%">
      <tr>
        <td style="background-color:#FFFFE0;"><b>what</b> &nbsp;</td>
        <td style="background-color:#E0E6F8;">a character vector giving the names of the Python objects,
    which should be attached to R.</td>
      </tr>
      <tr>
        <td style="background-color:#FFFFE0;"><b>env</b> &nbsp;</td>
        <td style="background-color:#E0E6F8;">the environment where the virtual Python objects are
               assigned to.</td>
      </tr>
    </table>

Examples
--------
.. code-block:: R

    if ( pyIsConnected() ){
    pyExec("import os")
    
    ## attach to global
    ## ----------------
    ## attach the function getcwd from the module os to R.
    pyAttach("os.getcwd", .GlobalEnv)
    os.getcwd
    os.getcwd()
    ## attach the string object os.name to R
    pyAttach("os.name", .GlobalEnv)
    pyExecp("os.name")
    os.name
    ## Since os.name is attached to the globalenv it can be set without using
    ## the global assignment operator
    os.name = "Hello Python from R!"
    pyExecp("os.name")
    os.name
    ## Please note if you don't pyAttach to globalenv you have to use
    ## the global assignment operator to set the values of the Python objects
    
    ## attach to a new environment
    ## ---------------------------
    os <- new.env()
    attach(os, name="python:os")
    pyAttach(paste("os", pyDir("os"), sep="."), as.environment("python:os"))
    os.sep
    os.sep = "new sep" ## this doesn't changes the value in Python but only
                       ## assigns the new variable os.sep to globalenv
    os.sep
    .GlobalEnv$`os.sep`
    as.environment("python:os")$`os.sep`
    pyExecp("os.sep")
    ls()
    ls("python:os")
    os.sep <<- "this changes the value in Python"
    .GlobalEnv$`os.sep`
    as.environment("python:os")$`os.sep`
    pyExecp("os.sep")
    }