Learned something really interesting. When you ask a question that starts with 'An é nach raibh.. ' You answer with 'Is ea nach raibh...'

I automatically expected 'Is é nach raibh...' to be the response.

So can I ask if it is always 'is ea' in response to 'an é' or is this a dialect thing at all? Or would 'is é' be acceptable too, but 'is ea' more often used?

Tá mearbhall orm faoin gceann seo.

Le ceist mar sin, bheadh mise ag súil leis an freagra a bheith diúltach.

"An é nach raibh"

"Bhí, ach"

Mar sin, nílim cinnte faoi do cheist. An bhfuil foinse iontaofa agat leis?

Tá an sampla seo ag na Bráithre:

Peadar: An é féin a rinne iad? Pól: Is é.

Fuair mé é seo freisin:

15.56 Cuirtear féidearthacht imthoisceach (is é sin gan ábaltacht gníomhaí a bheith i gceist) in iúl le leaganacha mar iad seo: an amhlaidh (an é, an ea) nach gcreideann tú mé? ní fios (níl a fhios, cá bhfios) cén uair a fhillfear; thiocfadh [dó] go bhfuil (raibh, etc.) siad ann; d'fhéadfadh [sé] go raibh siad ann; go bhféadfadh! an féidir go bhfuil tart ort? ní féidir go
dtiocfaidh (gur tháinig) sé; chomh luath agus is féidir; dá mb'fhéidir é.

I just came across this in Ciaran Mac Murchaidh's Cruinnscríobh:

Nuair a leanann forainm pearsanta (é, í, iad, mé/mise, srl.) an fhoirm cheisteach den Chopail (an/nach), bíonn an forainm sin sa fhreagra chomh maith.

Ceist: An í Bríd an múinteoir bunscoile s'againne?
Freagra: Is í

Má tá ainmfhocal éigin idir an fhoirm cheisteach den Chopail (an/nach) agus an forainm (é, í, iad, mé/mise, srl.)úsáidtear Is ea/Ní hea sa fhreagra:

C: An státseirbhíseach é d'athair
F: Is ea/Ní hea


But I think when it comes to a sentence like 'An é nach raibh a fhios agat?' the second 'is ea/ní hea' would apply, as there is an indefinite noun involved, rather than a sentence of identity

Does that sound right?

I don't know. I've never come across "an é nach x" except as a rhetorical device, which doesn't really expect an answer.

Aonghus and Sineadw, is "an é nach x" a colloquialism? I am wondering if it is really an abbreviated form of "an rud é nach x", thus naturally attracting the answer "is ea"?

Yeah I think there is an indefinite thing implied: 'an rud'. And yep, Aonghus, you dead right, it was a rhetorical question, but if you were to answer, I had been thinking that it had to be 'is é'.