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

Jens Alfke jens at mooseyard.com
Mon Aug 29 19:13:20 CDT 2016

> On Aug 29, 2016, at 4:38 PM, Zhao Xin <owenzx at gmail.com> wrote:
> ...
> _ = dict1.map {

I just use a `for` loop to iterate dict1, and inside it populate dict2. Using `map` here seems wasteful since it’s building an array that’s thrown away.

>     dict2.updateValue(value, forKey:key)

This is a tangent, but: Why do you use this syntax instead of the more readable `dict2[key] = value`? (I assume they’re equivalent internally.)

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