Rule:BlackIso

@RULE BlackIso

https://conwaylife.com/forums/viewtopic.php?p=154994#p154994

@COLORS 0 0 0 0 Space 1 0 128 255 Block 2 128 128 128 Tail 3 64 128 192 Block+Tail 4 255 255 255 Head 5 192 192 192 Head2 6 128 192 255 Push

@TABLE n_states:7 neighborhood:Moore symmetries:rotate4reflect var a={0,1,2,3,4,5,6} var b=a var c=a var d=a var e=a var f=a var g=a var h=a

var block={1,3} var tail={2,3} var S={4,5}

1. Through

 var A=block
 var B=A
 var C=tail 
 0 A,C,S,d,B,f,g,h 0
 0 A,1,S,d,B,f,g,1 S
 0 A,b,S,d,B,f,g,h 5

1. Push

 var A={0,1}
 0 S,A,c,d,1,f,g,A 5

 var A=tail
 var B=A
 6 1,b,c,d,1,f,g,h 5
 0 6,A,c,d,e,f,g,B 3
 0 6,A,c,d,e,f,g,h 0
 0 6,b,c,d,e,f,g,h 3

 6 1,b,2,d,2,f,2,h 1

 var C=block
 1 S,b,c,d,C,f,g,h 1
 1 S,A,c,d,e,f,g,h 1
 1 S,b,c,d,e,f,g,h 6

1. Reflect

 var A=tail
 S A,b,1,d,0,f,0,h 0

 1 1,4,A,d,e,f,g,h 1
 1 1,4,c,d,e,f,g,h 3

 0 1,4,A,d,e,f,g,h 0
 0 1,4,c,d,e,f,g,h 2

1. Moving

 0 S,A,c,d,e,f,g,h 0
 0 S,b,c,d,e,f,g,h 4

1. General

 6 a,b,c,d,e,f,g,h 4
 S a,b,c,d,e,f,g,h 2
 3 a,b,c,d,e,f,g,h 1

 # the tail persists without a head, marking the halt location
 var A={S, 6}
 2 A,b,c,d,e,f,g,h 0