[General] Commas and dashes

[Lakequeen]

In writing a work of fiction, is it ever permissable to use a dash after a comma?
As in: "Mary had no idea why the dogs, cats, and even the chickens, squawking madly, were were all running straight at her, but she knew, - better than most - it could only mean trouble.

 

[kfredson]

In writing a work of fiction, is it ever permissable to use a dash after a comma?
As in: "Mary had no idea why the dogs, cats, and even the chickens, squawking madly, were were all running straight at her, but she knew, - better than most - it could only mean trouble.

I think that very few people would even notice. In this case I would drop out the comma after "knew" -- and suggest to a student writer that she do the same -- but it is a very minor point.

 

[Raymott]

In writing a work of fiction, is it ever permissable to use a dash after a comma?
As in: "Mary had no idea why the dogs, cats, and even the chickens, squawking madly, were were all running straight at her, but she knew, - better than most - it could only mean trouble.

No, it's wrong, at least in this case. You should be able to remove a parenthetical phrase set off with dashes and still have a proper sentence.
But isn't your meaning "... she knew it could only mean trouble". Why do you think a comma is needed here?