How can I use a naming convention when converting checklist items to cards?

[Jacqui Douglas]

I've created a card button that will convert all checklist items to linked cards. How can I automate a naming convention that will give each name the title of the original / trigger card + the title of the checklist item it came from?

For example, if the original card was called Groceries and the checklist items were Apples, Bananas, Grapes, I'd want the new cards to be called Groceries: Apples, Groceries: Bananas etc. 

[Iain Dooley]

@Jacqui Douglas you can't do it during the conversion, but you can do it when a trello card is added as an attachment (you can use filtering to avoid this happening in all instances, for example if you copy labels from the parent card this means you can only execute when an attachment is added to a card containing a given label):