[swift-users] Mapping a Dictionary to a Dictionary?

Jens Alfke jens at mooseyard.com
Wed Aug 31 13:17:56 CDT 2016

> On Aug 31, 2016, at 10:51 AM, Daniel Tartaglia <danielt1263 at gmail.com> wrote:
> I use the below to do this:
> dict2 = dict1.map { $0.withUpdate($0.0, value: $0.1) }

I don’t see how this can work. Dictionary.map returns an Array, not a Dictionary.
Also, in the callback function $0 is the key, so your Dictionary.withUpdate method only makes sense if the key type of the Dictionary is another Dictionary, which seems … very unusual.

(To clarify, I wasn’t asking how to accomplish this; it’s pretty simple to write it either as an extension method or as a simple one-off ‘for’ loop. I was just making sure it wasn’t already in the standard library, since it seems an obvious thing to have.)

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-users/attachments/20160831/42a2ece6/attachment.html>

More information about the swift-users mailing list