Tactic to partially compute goal in Coq

Question

I have goal

quad X Y

, but I don't remember definition of "quad" and I don't want to start searching of its definition.

Is there a tactic that allow me rapidly substitute quad with its definition?

 Record quad (X Y:Type):= { x:X; y:Y}.

Or I have to remember and use

refine (@Build_quad _ _).

?

`constructor` should work is most cases. You may also find `Hint Constructors` useful. — ejgallego, Jun 01 '16 at 08:10
Btw, search in this case is not necessary, but it's rather simple: `Print quad.` will give you the desired information. If you're using ProofGeneral, you need to move the cursor (point) over the entity of interest and hit `C-c C-a C-p` and `Enter`. — Anton Trunov, Jun 01 '16 at 08:59

score 3 · Accepted Answer · answered Jun 01 '16 at 08:45

3

Your slightly mistaken, Build_quad is not the definition of quad, it is its constructor. It creates terms of type quad. As @ejgallego said, you should use the constructor tactic in this situation.

Your goal wants you to provide a term of type quad X Y, and the only way to build such a term from scratch is to use the constructor Build_quad of type forall X Y: Type, X -> Y -> quad X Y.

answered Jun 01 '16 at 08:45

Vinz

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For the sake of completeness: a less automated way would be to `apply Build_quad.` instead of using `constructor.` – Anton Trunov Jun 01 '16 at 09:17
1

Usually I use `split` for records. – eponier Jun 02 '16 at 08:32

Tactic to partially compute goal in Coq

1 Answers1