Re: map destructuring with defaults

2011-01-06 Thread Alan
No, no new map is created. The :or clause simply creates the local
binding for you if none existed in the map; there's no need for it to
create a second map to do this.

On Jan 6, 6:27 pm, Seth  wrote:
> Ah. But a new map is being created with the default :or operation. I
> guess the ability to get this entire map with defaults is not
> available directly from clojure destructuring binding.

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Re: map destructuring with defaults

2011-01-06 Thread Seth
Ah. But a new map is being created with the default :or operation. I
guess the ability to get this entire map with defaults is not
available directly from clojure destructuring binding.

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Re: map destructuring with defaults

2011-01-04 Thread Chas Emerick
The :as option in destructuring forms binds the original value being 
destructured -- no "entire" map is being formed in the background ahead of time.

So, build that "entire" map as you require; e.g.:

=> (let [{:keys [a] :as b} (merge {:b 3} {:a 4})] b)
{:a 4, :b 3}

- Chas

On Jan 4, 2011, at 7:38 PM, Seth wrote:

> Is there any way to get the entire map when destructuring plus the
> defaults?
> (let [{:keys [a] :or {a 4} :as b} {:b 3}] b)
> returns {:b 3}
> 
> but i would like it to return {:b 3 :a 4}
> 
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