Autocompletion
The autocompletion functionality saves time and mitigates the risk of typographical errors.
What is autocompletion?
Autocompletion refer to the action of pressing the tabulation key after typing the first few characters of a command name or filepath, allowing the Terminal application to predict the rest of the word.
If the prediction unambiguously identifies a single match, the remaining characters are automatically inserted to complete the word. The user can then continue typing the rest of the command or filepath.
If the prediction identifies multiple matches, no autocompletion will take place.
Instead, the tabulation key can be pressed a second time to reveal the list
of ambiguous matches that were identified.
If the list of matches identified is excessively large, the terminal
may prompt for a y or n answer, whether to display all the possibilities.
Either way, the prompt will be returned with the characters typed so far,
encouraging the user to type more characters before attempting to autocomplete
again.
The tabulation key
The tabulation key is located on the left side of most keyboards, above the Caps Lock key.
Why use autocompletion?
The first and most obvious benefit of autocompletion is the time saved automatically completing words at the touch of the tabulation key instead of manually typing every single character of every command.
Meanwhile, a more subtle yet unbdoubtedly more impactful benefit of autocompletion is the mitigation of typographical mistakes introduced by human error during the manual typing of commands, leading to time saved not running commands that would have otherwise failed due to typographical errors.
Instead, autocompletion acts as a dynamic sanity check that can be used to reveal whether the characters typed so far match the expected command or file path. In particular, autocompletion failing to identify any match is usually taken as a sign that a typographical error is present in the characters typed so far, prompting users to pause and proofread themselves.
While the rest of this documentation does not explicitly refer to autocompletion, we encourage you to try it out and practice it regularly to build it into your habits as a Bash user on the CCB cluster.