K_KPLUS (reference) in projects: vim-8.2.3635

399 #define K_KPLUS		TERMCAP2KEY('K', '6')	// keypad plus  macro

989     {K_KPLUS,		(char_u *)"kPlus"},

1447 	case K_KPLUS:		key = VTERM_KEY_KP_PLUS; break;  in term_convert_key()

/vim-8.2.3635/src/
H A D	keymap.h	`399 #define K_KPLUS TERMCAP2KEY('K', '6') // keypad plus macro`
H A D	term.c	`670 {K_KPLUS, "\316N"}, 771 {K_KPLUS, IF_EB("\033Ok", ESC_STR "Ok")}, // keypad plus 965 {K_KPLUS, IF_EB("\033Ok", ESC_STR "Ok")}, // keypad plus 1297 {K_KPLUS, "[KPLUS]"},`
H A D	misc2.c	`989 {K_KPLUS, (char_u *)"kPlus"},`
H A D	getchar.c	`1777 case K_KPLUS: c = '+'; break; in vgetc()`
H A D	terminal.c	`1447 case K_KPLUS: key = VTERM_KEY_KP_PLUS; break; in term_convert_key()`