About the explanation of the ⊸ ⊢ rule
The ⊸ ⊢ rule can be simplified to say that if one transaction produces an A for free and another transaction produces nothing for B, then we can combine both transactions together with a third transaction that can produce a B from an A.
If "for free" and "nothing for" is used in the explanation,
isn't it is about the rule without context?
| Assumptions |
Conclusion |
Rule |
| ⊢ A |
|
⊸ ⊢ |
| B ⊢ Λ |
A ⊸ B ⊢ |
|
Which is only a special case of the rule with context:
| Assumptions |
Conclusion |
Rule |
| Γ ⊢ A, Δ |
|
⊸ ⊢ |
| Θ, B ⊢ Λ |
Γ, Θ, A ⊸ B ⊢ Δ, Λ |
|