hi everybody.

I have two problems I enc= ountered while proving something.
I'm bringing them here = in a very simplified form.
I'm working with Isabelle/jEdi= t 2018 on win10.

1) here there is e= xternal lemma which is not really important,=C2=A0
so I simplifie= d it to "Y=3DY".
inside the proof there is a lemma L7 w= hose proof is again not important,
so I used "sorry".
the problem comes in the "apply" statement where the cur= sor stands.
for some reason the simplifier can't apply L7, an= d I don't know why.
maybe you know?

=

2. it seems I can = solve the first problem by applying 'subst' and 'auto' inst= ead of 'simp'.
but when I'm trying to continue the eq= uality, before even applying anything,
I get some typing problem = I don't understand. maybe you do.

=

I'm attaching the text fil= es just in case.

 Virus-free. www.avast.com
hi everybody.
(I'm sending this mail again with '[Isabelle]' in the subje= ct. sorry for the mess.)

I have t= wo problems I encountered while proving something.
I'm br= inging them here in a very simplified form.
I'm working w= ith Isabelle/jEdit 2018 on win10.

1= ) here there is external lemma which is not really important,=C2=A0
so I simplified it to "Y=3DY".
inside the proof ther= e is a lemma L7 whose proof is again not important,
so I used &qu= ot;sorry".
the problem comes in the "apply" statem= ent where the cursor stands.
for some reason the simplifier can&#= 39;t apply L7, and I don't know why.
maybe you know?

2. it seems I can solve the first problem by applying 'sub= st' and 'auto' instead of 'simp'.
but when I&= #39;m trying to continue the equality, before even applying anything,
=
I get some typing problem I don't understand. maybe you do.
<= div>

=
I'm attaching the text files just in case.
tha= nx in advance.