fn closest_monster(tcod: &Tcod, objects: &[Object], max_range: i32) -> Option<usize> {
    let mut closest_enemy = None;
    let mut closest_dist = (max_range + 1) as f32; // start with (slightly more than) maximum range

    for (id, object) in objects.iter().enumerate() {
        if (id != PLAYER)
            && object.fighter.is_some()
            && object.ai.is_some()
            && tcod.fov.is_in_fov(object.x, object.y)
        {
            // calculate distance between this object and the player
            let dist = objects[PLAYER].distance_to(object);
            if dist < closest_dist {
                // it's closer, so remember it
                closest_enemy = Some(id);
                closest_dist = dist;
            }
        }
    }
    closest_enemy
}
/// find closest enemy, up to a maximum range, and in the player's FOV
find closest enemy, up to a maximum range, and in the player's FOV
find closest enemy up to a maximum range and in the player ' s FOV
fn closest_monster(tcod: &Tcod, objects: &[Object], max_range: i32) -> Option<usize> {
    let mut closest_enemy = None;
    let mut closest_dist = (max_range + 1) as f32; // start with (slightly more than) maximum range
    for (id, object) in objects.iter().enumerate() {
        if (id != PLAYER)
            && object.fighter.is_some()
            && object.ai.is_some()
            && tcod.fov.is_in_fov(object.x, object.y)
        {
            // calculate distance between this object and the player
            let dist = objects[PLAYER].distance_to(object);
            if dist < closest_dist {
                // it's closer, so remember it
                closest_enemy = Some(id);
                closest_dist = dist;
            }
        }
    }
    closest_enemy
}
fn closest_monster ( tcod : & Tcod , objects : & [ Object ] , max_range : i32 ) -> Option < usize > { let mut closest_enemy = None ; let mut closest_dist = ( max_range + 1 ) as f32 ; // start with (slightly more than) maximum range for ( id , object ) in objects . iter ( ) . enumerate ( ) { if ( id != PLAYER ) && object . fighter . is_some ( ) && object . ai . is_some ( ) && tcod . fov . is_in_fov ( object . x , object . y ) { // calculate distance between this object and the player let dist = objects [ PLAYER ] . distance_to ( object ) ; if dist < closest_dist { // it's closer, so remember it closest_enemy = Some ( id ) ; closest_dist = dist ; } } } closest_enemy }
find closest enemy, up to a maximum range, and in the player's FOV
find closest enemy up to a maximum range and in the player ' s FOV
tcod
&Tcod
objects
&[Object]
max_range
i32