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flying-sheep edited this page Jan 18, 2012 · 4 revisions

I’m currently working on PyRepl. Since many of my project never see the light of the day, i present you the approach and skeleton of it: The finished project would have many convenience functions built around the js function.

import sys, re
from telnetlib import Telnet

class Mozrepl(object):
    def __init__(self, ip="", port=4242):
        self.ip = ip
        self.port = port
        self.prompt = b"repl>"

    def __enter__(self):
        self.t = Telnet(self.ip, self.port)
        intro = self.t.read_until(self.prompt, 1)
        if not intro.endswith(self.prompt):
            self.prompt ="repl\d+>", intro).group(0)
            print("Waited due to nonstandard prompt:", self.prompt.decode())
        return self

    def __exit__(self, type, value, traceback):
        del self.t

    def js(self, command):
        self.t.write(command.encode() + b"\n")
        return self.t.read_until(self.prompt).decode()


You can use the with statement to create a telnet connection like this:

with Mozrepl() as mozrepl:

alternatively, use the connection machanism manually:

mozrepl = Mozrepl().__enter__()




  • create new telnet sessions via __enter__ and __exit__ that can be used in parallel
  • expose repl’s functions in the Mozrepl class by parsing the output of inspect and doc
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