Allow formats to be specified as functions (in the code) so they are only evaluated on demand rather than each time a format tree is constructed. Use this for expensive formats like pane_current_command.
Allow formats to be specified as functions (in the code) so they are
only evaluated on demand rather than each time a format tree is
constructed. Use this for expensive formats like pane_current_command.

klaxalk/tmux,klaxalk/tmux,klaxalk/tmux,klaxalk/tmux,klaxalk/tmux