Keyboard Shortcuts

You may try with this demo http://repo.cirru.org/respo-cirru-editor

On token

Shortcut	Meaning
Space	add token after focus
Shift Space	insert token before focus
Tab	fold focused token
Shift Tab	unfold expression with only 1 token
Enter	add token after focus
Shift Enter	insert token before focus
Backspace	remove focused token if empty
Up	move to parent expression
Left	move to previous brother node accordingly
Right	move to next brother node accordingly

On expression

Shortcut	Meaning
Space	add token after focused expression(special behavoir at root)
Shift Space	insert token before focused expression
Tab	fold focused expression
Shift Tab	unfold focused expression
Enter	add expression after focused expression
Shift Enter	insert expression after focused expression
Command Enter	prepend token inside focused expression
Command Shift Enter	append token inside focused expression
Backspace	remove focused expression
Left	move to previous brother node
Right	move to next brother node
Up	move to parent expression
Down	move to first child
Command b	duplicate focused expression
Command c	copy focused expression
Command x	cut focused expression
Command v	paste to focused expression
Command Shift f	fold/unfold focused expression