(I’m aware this isn’t exactly what you’re asking for, but) If you’re happy with the auto-completion/suggestions appearing on TAB (as used in many shells), then you can quickly get up and running using the readline module.
Here’s a quick example based on Doug Hellmann’s PyMOTW writeup on readline.
import readline
class MyCompleter(object): # Custom completer
def __init__(self, options):
self.options = sorted(options)
def complete(self, text, state):
if state == 0: # on first trigger, build possible matches
if text: # cache matches (entries that start with entered text)
self.matches = [s for s in self.options
if s and s.startswith(text)]
else: # no text entered, all matches possible
self.matches = self.options[:]
# return match indexed by state
try:
return self.matches[state]
except IndexError:
return None
completer = MyCompleter(["hello", "hi", "how are you", "goodbye", "great"])
readline.set_completer(completer.complete)
readline.parse_and_bind('tab: complete')
input = raw_input("Input: ")
print "You entered", input
This results in the following behaviour (<TAB> representing a the tab key being pressed):
Input: <TAB><TAB>
goodbye great hello hi how are you
Input: h<TAB><TAB>
hello hi how are you
Input: ho<TAB>ow are you
In the last line (HOTAB entered), there is only one possible match and the whole sentence “how are you” is auto completed.
Check out the linked articles for more information on readline.
“And better yet would be if it would complete words not only from the beginning … completion from arbitrary part of the string.”
This can be achieved by simply modifying the match criteria in the completer function, ie. from:
self.matches = [s for s in self.options
if s and s.startswith(text)]
to something like:
self.matches = [s for s in self.options
if text in s]
This will give you the following behaviour:
Input: <TAB><TAB>
goodbye great hello hi how are you
Input: o<TAB><TAB>
goodbye hello how are you
Updates: using the history buffer (as mentioned in comments)
A simple way to create a pseudo-menu for scrolling/searching is to load the keywords into the history buffer. You will then be able to scroll through the entries using the up/down arrow keys as well as use Ctrl+R to perform a reverse-search.
To try this out, make the following changes:
keywords = ["hello", "hi", "how are you", "goodbye", "great"]
completer = MyCompleter(keywords)
readline.set_completer(completer.complete)
readline.parse_and_bind('tab: complete')
for kw in keywords:
readline.add_history(kw)
input = raw_input("Input: ")
print "You entered", input
When you run the script, try typing Ctrl+r followed by a. That will return the first match that contains “a”. Enter Ctrl+r again for the next match. To select an entry, press ENTER.
Also try using the UP/DOWN keys to scroll through the keywords.