SEL_EXISTS
#define IS_SEL_EXISTS(scr) ((scr)->mouse_flags & SEL_EXISTS)
if (ISSET(scr->mouse_flags, SEL_EXISTS))
SET(scr->mouse_flags, SEL_IN_PROGRESS | SEL_EXISTS | SEL_BY_CHAR);
if (ISSET(scr->mouse_flags, SEL_EXISTS))
SET(scr->mouse_flags, SEL_IN_PROGRESS | SEL_EXISTS | SEL_BY_WORD);
if (ISSET(scr->mouse_flags, SEL_EXISTS))
SET(scr->mouse_flags, SEL_IN_PROGRESS | SEL_EXISTS | SEL_BY_LINE);
SET(scr->mouse_flags, SEL_IN_PROGRESS | SEL_EXISTS);
if (ISSET(scr->mouse_flags, SEL_EXISTS)) {
CLR(scr->mouse_flags, SEL_IN_PROGRESS | SEL_EXISTS);
if (ISSET(scr->mouse_flags, SEL_EXISTS))