The Tab Key
The action of the tab key depends on the Editor > Keyboard > Personality preference, the file type being edited, and the position within the file.
To insert a real tab character, press Ctrl-T.
Tab Key Action
The behavior of the tab key can be altered with the User Interface > Keyboard > Tab Key Action preference, which provides the following options:
Default for Personality selects from the other tab key actions below, according to the current keyboard personality and file type. In all non-Python files, the default is Move to Next Tab Stop. In Python files, the defaults are as follows:
Normal: Smart Tab
VI/VIM: Move to Next Tab Stop
Emacs: Indent to Match
Brief: Smart Tab
Visual Studio: Move to Next Tab Stop
macOS: Smart Tab
Eclipse: Emulates Eclipse
XCode: Smart Tab
MATLAB: Insert Tab Character
Indent to Match indents the current line or selected lines to position them at the computed indent level for their context in the file.
Move to Next Tab Stop enters indentation so that the caret reaches the next tab stop.
Indent Region increases the indentation of the current line or selected lines by one level.
Insert Tab Character inserts a Tab character chr(9) into the file.
Smart Tab is equivalent to Move to Next Tab Stop in non-Python files, and implements the following behavior in Python files:
(1) When the caret is within a line or there is a non-empty selection, this performs Indent to Match. When the line or lines are already at the matching position, indentation is toggled between other valid positions.
(2) When the caret is at the end of a non-empty line and there is no selection, one indent level is inserted. The User Interface > Keyboard > Smart Tab End of Line Indents preference alters the type of indentation used in this case, or disables this aspect of the Smart Tab feature.
