comint: show the original input when match-cycling through history

Question

Currently, I have bindings for comint-previous-matching-input-from-input and comint-next-matching-input-from-input.

My problem is this. Suppose I am on a prompt with some text (say, "x = ") and issue previous - the latest command shows up (e.g. "x = 10"). But now, when I issue next, nothing happens. I understand - no input is matched, so the latest command stays. Instead, I want the original text to show up ("x = ") (if you are familiar with zsh input completion, this is it).

How can I do this?

Answer 1

I cycle using comint-previous-input and comint-next-input. So, if I had entered previously x = 1 and x = 2; when I enter x = [cursor] the above two comint commands cycle the previous entries backward and forward. But it won't go back to x = as it is not in the history. You can just kill to the end of line at any point to get x = again.