Context: using Enthought's Canopy Version: 1.7.4.3348 (64 bit) on Windows 10.
Typing into the python shell, errors produce a "...:" prompt, which I can then not break out of. Hitting enter and trying other ideas sadly leads to a repeat of the same prompt. How to break out of this mode, and get on with debugging?
EDITED, see bottom of answer
The key point to understand is that when IPython prompts you with
..., it is because you are in the middle of typing a multi-line statement (whether that was your intention or not). Typically this is because on some previous line, you typed a left parenthesis (or bracket), or a triple-quote-mark, etc and IPython is waiting for you to complete your statement with a right parenthesis or matching triple-quote, etc.So what you probably want to do is simply to erase your partially entered statement. The easiest way to do this, assuming that your cursor is already at the end of the last line in your multi-line statement, is just to press and hold the backspace key until your statement is all erased. Slightly quicker is to do the same with Ctrl+Backspace, which erases a word at a time instead of a character at a time. After you've erased all the garbage, press
Enter, not actually needed but it will make you feel better, to convince yourself that everything is back to normal.(BTW, the fact that you were actually in the middle of typing a single long statement also explains why typing "quit" does nothing; you are not really typing a "quit" command, but just typing the additional letters "quit" into the middle of your already too-long and erroneous command, whatever that might be, which makes it even longer and more erroneous!
As a further side note --
quitis actually not very useful in Canopy's IPython panel, because it just closes the panel but doesn't really close down IPython; if you reopen the panel from the View menu, it is still just as you left it. If you really want to restart IPython (clear all your variables and imports), do it with the "Restart kernel" command in Canopy's Run menu.)EDIT:
OP's screen shots, sent privately, showed that Autodebug mode was on (this is the bulls-eye-like icon on the toolbar.) The solution was to toggle off Autodebug.
Background: Autodebug hooks into the channel between Canopy's IPython (QtConsole) front end, and the IPython kernel back end. If autodebug is left on, some problems can break this channel. This should be improved in Canopy 2.0, currently in alpha internally.