change Atom keybinding behavior depending on character near cursor

Question

In the Atom text editor, how can I make a keybinding take a different action depending on which character is immediately to the left of the cursor?

In particular:

• if the character immediately to the left of the cursor is a whitespace character, then I want the tab key to insert indentation.
• if the character immediately to the left of the cursor is not whitespace, then I want the tab key to open the autocomplete pane.

Answer 1

you can extend this extension https://github.com/atom/autocomplete-plus.git.

first git clone the repo, remove the extension from your atom if you had it, then cd to your cloned directory, then install it using apm link

in the https://github.com/atom/autocomplete-plus/blob/master/keymaps/autocomplete-plus.cson you can add the tab :

'atom-text-editor':
  'ctrl-space': 'autocomplete-plus:activate',
  'tab': 'autocomplete-plus:activate',

and here line 501 ,before entering the while loop, you can check if the last character is equal space

if(line[position.column - 1] == ' '){
    this.editor.indent()
}

and add one level Indentation .