repl_session

$ # An example REPL session
$ python3 interpret.py
Python [REDACTED] (default, [REDACTED])
[REDACTED] on [REDACTED]
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> 10
10
>>> repr_map['int'] = bin
>>> 10
0b1010

repr_map_interactive.py

import ast
import code
import codeop


repr_map = {}


def _wrap_repr(thing):
	class AdHocWrapper(type(thing)):
		def __repr__(self):
			global repr_map
			try:
				return repr_map[thing.__class__.__name__](self)
			except KeyError:
				return super().__repr__()

	return AdHocWrapper(thing)


REPL_EXPORT = { "_wrap_repr": _wrap_repr, "repr_map": repr_map }


class RewriteConstants(ast.NodeTransformer):

	def visit_Constant(self, node):
		return ast.Call(
				func=ast.Name(
					id="_wrap_repr",
					ctx=ast.Load()),
				args=[node],
				keywords=[])

	visit_Num = visit_Constant
	visit_Str = visit_Constant
	visit_Bytes = visit_Constant


class TransformCompile():

	def __init__(self, transformers):
		self.transformers = transformers
		self.inferior = codeop.Compile()

	def __call__(self, source, filename, symbol):
		tree = compile(source, filename, symbol, ast.PyCF_ONLY_AST|0x200, True)
		for trans in self.transformers:
			ast.fix_missing_locations(trans.visit(tree))

		return self.inferior(tree, filename, symbol)


if __name__ == "__main__":
	console = code.InteractiveConsole(REPL_EXPORT)
	console.compile.compiler = TransformCompile([RewriteConstants()])
	console.interact()