Selects an item in the completion popupmenu. If |ins-completion| is not active this API call is silently ignored. Useful for an external UI using |ui-popupmenu| to control the popupmenu with the mouse. Can also be used in a mapping; use |:map-cmd| to ensure the mapping doesn't end completion mode. Parameters: ~ {item} Index (zero-based) of the item to select. Value of -1 selects nothing and restores the original text. {insert} Whether the selection should be inserted in the buffer. {finish} Finish the completion and dismiss the popupmenu. Implies insert . {opts} Optional parameters. Reserved for future use.