| Step | Hyp | Ref | Expression | 
						
							| 0 |  | ce1 | ⊢ eval1 | 
						
							| 1 |  | vr | ⊢ 𝑟 | 
						
							| 2 |  | cvv | ⊢ V | 
						
							| 3 |  | cbs | ⊢ Base | 
						
							| 4 | 1 | cv | ⊢ 𝑟 | 
						
							| 5 | 4 3 | cfv | ⊢ ( Base ‘ 𝑟 ) | 
						
							| 6 |  | vb | ⊢ 𝑏 | 
						
							| 7 |  | vx | ⊢ 𝑥 | 
						
							| 8 | 6 | cv | ⊢ 𝑏 | 
						
							| 9 |  | cmap | ⊢  ↑m | 
						
							| 10 |  | c1o | ⊢ 1o | 
						
							| 11 | 8 10 9 | co | ⊢ ( 𝑏  ↑m  1o ) | 
						
							| 12 | 8 11 9 | co | ⊢ ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) ) | 
						
							| 13 | 7 | cv | ⊢ 𝑥 | 
						
							| 14 |  | vy | ⊢ 𝑦 | 
						
							| 15 | 14 | cv | ⊢ 𝑦 | 
						
							| 16 | 15 | csn | ⊢ { 𝑦 } | 
						
							| 17 | 10 16 | cxp | ⊢ ( 1o  ×  { 𝑦 } ) | 
						
							| 18 | 14 8 17 | cmpt | ⊢ ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) | 
						
							| 19 | 13 18 | ccom | ⊢ ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) | 
						
							| 20 | 7 12 19 | cmpt | ⊢ ( 𝑥  ∈  ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) )  ↦  ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) ) | 
						
							| 21 |  | cevl | ⊢  eval | 
						
							| 22 | 10 4 21 | co | ⊢ ( 1o  eval  𝑟 ) | 
						
							| 23 | 20 22 | ccom | ⊢ ( ( 𝑥  ∈  ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) )  ↦  ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) )  ∘  ( 1o  eval  𝑟 ) ) | 
						
							| 24 | 6 5 23 | csb | ⊢ ⦋ ( Base ‘ 𝑟 )  /  𝑏 ⦌ ( ( 𝑥  ∈  ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) )  ↦  ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) )  ∘  ( 1o  eval  𝑟 ) ) | 
						
							| 25 | 1 2 24 | cmpt | ⊢ ( 𝑟  ∈  V  ↦  ⦋ ( Base ‘ 𝑟 )  /  𝑏 ⦌ ( ( 𝑥  ∈  ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) )  ↦  ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) )  ∘  ( 1o  eval  𝑟 ) ) ) | 
						
							| 26 | 0 25 | wceq | ⊢ eval1  =  ( 𝑟  ∈  V  ↦  ⦋ ( Base ‘ 𝑟 )  /  𝑏 ⦌ ( ( 𝑥  ∈  ( 𝑏  ↑m  ( 𝑏  ↑m  1o ) )  ↦  ( 𝑥  ∘  ( 𝑦  ∈  𝑏  ↦  ( 1o  ×  { 𝑦 } ) ) ) )  ∘  ( 1o  eval  𝑟 ) ) ) |