Currently auto completes can be committed by pressing Enter and/or Tab, depending on the "auto_complete_commit_on_tab" setting. Expand this by adding a "auto_complete_commit_trigger_characters" setting which allows the user to specify which characters act as auto complete commit triggers.
For instance if working with Python I might like to set it as:
"auto_complete_commit_trigger_characters": [".", " ", "Tab"]
.. and use Esc when I want to cancel auto complete.
A similar option is found in Eclipse, where it gives the user a nice, fine-grained control over how "aggressive" the auto complete behavior is. In particular, allowing non-alphanumeric characters such as ".", ">", and " " to trigger auto complete commit can noticeably increase coding efficiency in some circumstances.
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