A short example implementation

This notebook demonstrates how one can use the widgets already built in to IPython to create a working variable inspector much like the ones seen in popular commercial scientific computing environments.



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import ipywidgets as widgets # Loads the Widget framework.
from IPython.core.magics.namespace import NamespaceMagics # Used to query namespace.

# For this example, hide these names, just to avoid polluting the namespace further
get_ipython().user_ns_hidden['widgets'] = widgets
get_ipython().user_ns_hidden['NamespaceMagics'] = NamespaceMagics



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class VariableInspectorWindow(object):
    instance = None
    
    def __init__(self, ipython):
        """Public constructor."""
        if VariableInspectorWindow.instance is not None:
            raise Exception("""Only one instance of the Variable Inspector can exist at a 
                time.  Call close() on the active instance before creating a new instance.
                If you have lost the handle to the active instance, you can re-obtain it
                via `VariableInspectorWindow.instance`.""")
        
        VariableInspectorWindow.instance = self
        self.closed = False
        self.namespace = NamespaceMagics()
        self.namespace.shell = ipython.kernel.shell
        
        self._box = widgets.Box()
        self._box.layout.overflow = 'visible scroll'
        self._table = widgets.HTML(value = 'Not hooked')
        self._box.children = [self._table]
        
        self._ipython = ipython
        self._ipython.events.register('post_run_cell', self._fill)
        
    def close(self):
        """Close and remove hooks."""
        if not self.closed:
            self._ipython.events.unregister('post_run_cell', self._fill)
            self._box.close()
            self.closed = True
            VariableInspectorWindow.instance = None

    def _fill(self):
        """Fill self with variable information."""
        values = self.namespace.who_ls()
        self._table.value = '<div class="rendered_html jp-RenderedHTMLCommon"><table><thead><tr><th>Name</th><th>Type</th><th>Value</th></tr></thead><tr><td>' + \
            '</td></tr><tr><td>'.join(['{0}</td><td>{1}</td><td>{2}'.format(v, type(eval(v)).__name__, str(eval(v))) for v in values]) + \
            '</td></tr></table></div>'

    def _repr_mimebundle_(self, **kwargs):
        return self._box._repr_mimebundle_(**kwargs)



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inspector = VariableInspectorWindow(get_ipython())
inspector

Test



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a = 5



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b = 3.0



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c = a * b



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d = "String"



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del b



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inspector.close()



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Variable Inspector Widget

A short example implementation

Test