Defining Part 1 - Code cleanup toward defines (#19262)

* This is only the beginning

* Update stack.dm

code/game/objects/structures/aliens.dm

@@ -129,7 +129,7 @@
 /obj/structure/alien/weeds/New(pos, node)
 	..()
 	linked_node = node
-	if(istype(loc, /turf/space))
+	if(isspaceturf(loc))
 		qdel(src)
 		return
 	if(icon_state == "weeds")
@@ -146,7 +146,7 @@
 /obj/structure/alien/weeds/proc/Life()
 	var/turf/U = get_turf(src)
 
-	if(istype(U, /turf/space))
+	if(isspaceturf(U))
 		qdel(src)
 		return
 
@@ -155,7 +155,7 @@
 
 	for(var/turf/T in U.GetAtmosAdjacentTurfs())
 
-		if(locate(/obj/structure/alien/weeds) in T || istype(T, /turf/space))
+		if(locate(/obj/structure/alien/weeds) in T || isspaceturf(T))
 			continue
 
 		new /obj/structure/alien/weeds(T, linked_node)

code/game/objects/structures/crates_lockers/closets/cardboardbox.dm

@@ -71,7 +71,7 @@
 				M.show_message("<span class='notice'>\The [src] has been cut apart by [user] with \the [WC].</span>", 3, "You hear cutting.", 2)
 			qdel(src)
 			return
-		if(istype(W, /obj/item/pen))
+		if(is_pen(W))
 			var/decalselection = input("Please select a decal") as null|anything in list("Atmospherics", "Bartender", "Barber", "Blueshield", "Captain",
 			"Cargo", "Chief Engineer",	"Chaplain",	"Chef", "Chemist", "Assistant", "Clown", "CMO", "Coroner", "Detective", "Engineering", "Genetics", "HOP",
 			"HOS", "Hydroponics", "Internal Affairs Agent", "Janitor",	"Magistrate", "Medical", "Mime", "Mining", "NT Representative", "Paramedic",

code/game/objects/structures/crates_lockers/closets/fireaxe.dm

@@ -39,7 +39,7 @@
 				to_chat(user, "<span class = 'caution'> You disable the locking modules.</span>")
 				update_icon(UPDATE_ICON_STATE)
 			return
-		else if(istype(O, /obj/item))
+		else if(isitem(O))
 			user.changeNext_move(CLICK_CD_MELEE)
 			var/obj/item/W = O
 			if(smashed || localopened)

code/game/objects/structures/door_assembly.dm

@@ -57,7 +57,7 @@
 		. += "<span class='notice'>There is a small <i>paper</i> placard on the assembly[doorname].</span>"
 
 /obj/structure/door_assembly/attackby(obj/item/W, mob/user, params)
-	if(istype(W, /obj/item/pen))
+	if(is_pen(W))
 		// The door assembly gets renamed to "Assembly - Foobar",
 		// but the `t` returned from the proc is just "Foobar" without the prefix.
 		var/t = rename_interactive(user, W)

code/game/objects/structures/false_walls.dm

@@ -128,7 +128,7 @@
 		to_chat(user, "<span class='warning'>[src] is blocked!</span>")
 		return TRUE
 
-	if(!istype(T, /turf/simulated/floor))
+	if(!isfloorturf(T))
 		to_chat(user, "<span class='warning'>[src] bolts must be tightened on the floor!</span>")
 		return TRUE
 	user.visible_message("<span class='notice'>[user] tightens some bolts on the wall.</span>", "<span class='warning'>You tighten the bolts on the wall.</span>")

code/game/objects/structures/grille.dm

@@ -156,7 +156,7 @@
 	deconstruct()
 
 /obj/structure/grille/screwdriver_act(mob/user, obj/item/I)
-	if(!(anchored || istype(loc, /turf/simulated) || locate(/obj/structure/lattice) in get_turf(src)))
+	if(!(anchored || issimulatedturf(loc) || locate(/obj/structure/lattice) in get_turf(src)))
 		return
 	. = TRUE
 	if(shock(user, 90))

code/game/objects/structures/inflatable.dm

@@ -148,7 +148,7 @@
 					operate()
 			else
 				operate()
-	else if(istype(user, /obj/mecha))
+	else if(ismecha(user))
 		operate()
 
 /obj/structure/inflatable/door/proc/operate()

code/game/objects/structures/mineral_doors.dm

@@ -78,7 +78,7 @@
 					operate()
 			else
 				operate()
-	else if(istype(user, /obj/mecha))
+	else if(ismecha(user))
 		operate()
 
 /obj/structure/mineral_door/proc/operate()

code/game/objects/structures/morgue.dm

@@ -133,7 +133,7 @@
 	return
 
 /obj/structure/morgue/attackby(P as obj, mob/user as mob, params)
-	if(istype(P, /obj/item/pen))
+	if(is_pen(P))
 		var/t = rename_interactive(user, P)
 
 		if(isnull(t))
@@ -355,7 +355,7 @@ GLOBAL_LIST_EMPTY(crematoriums)
 	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/crematorium/attackby(P as obj, mob/user as mob, params)
-	if(istype(P, /obj/item/pen))
+	if(is_pen(P))
 		rename_interactive(user, P)
 		add_fingerprint(user)
 		return

code/game/objects/structures/noticeboard.dm

@@ -65,11 +65,11 @@
 		var/obj/item/P = locate(href_list["write"])
 
 		if((P && P.loc == src)) //ifthe paper's on the board
-			if(istype(usr.r_hand, /obj/item/pen)) //and you're holding a pen
+			if(is_pen(usr.r_hand)) //and you're holding a pen
 				add_fingerprint(usr)
 				P.attackby(usr.r_hand, usr) //then do ittttt
 			else
-				if(istype(usr.l_hand, /obj/item/pen)) //check other hand for pen
+				if(is_pen(usr.l_hand)) //check other hand for pen
 					add_fingerprint(usr)
 					P.attackby(usr.l_hand, usr)
 				else

code/game/objects/structures/stool_bed_chair_nest/wheelchair.dm

@@ -88,7 +88,7 @@
 		occupant.Weaken(12 SECONDS)
 		occupant.Stuttering(12 SECONDS)
 		playsound(src.loc, 'sound/weapons/punch1.ogg', 50, 1, -1)
-		if(istype(A, /mob/living))
+		if(isliving(A))
 			var/mob/living/victim = A
 			victim.Weaken(12 SECONDS)
 			victim.Stuttering(12 SECONDS)

code/game/objects/structures/tables_racks.dm

@@ -177,7 +177,7 @@
 
 /obj/structure/table/MouseDrop_T(obj/O, mob/user)
 	..()
-	if((!( istype(O, /obj/item) ) || user.get_active_hand() != O))
+	if((!( isitem(O) ) || user.get_active_hand() != O))
 		return
 	if(isrobot(user))
 		return
@@ -841,7 +841,7 @@
 		. = . || mover.checkpass(PASSTABLE)
 
 /obj/structure/rack/MouseDrop_T(obj/O, mob/user)
-	if((!( istype(O, /obj/item) ) || user.get_active_hand() != O))
+	if((!( isitem(O) ) || user.get_active_hand() != O))
 		return
 	if(isrobot(user))
 		return

code/game/objects/structures/windoor_assembly.dm

@@ -165,7 +165,7 @@
 				else
 					W.forceMove(loc)
 
-			else if(istype(W, /obj/item/pen))
+			else if(is_pen(W))
 				var/t = rename_interactive(user, W)
 				if(!isnull(t))
 					created_name = t