A common pattern that I've found myself using is having to prefix a few
keys (namely `ids`) which I do with following approach:
```
%{}
|> Map.put(:prefix_key_1, map.key_1)
|> Map.put(:prefix_key_2, map.key_2)
=> %{prefix_key_1: :val_1, prefix_key_2: :val_2}
```
or
```
%{prefix_key_1: map.key_1, prefix_key_2: map.key_2}
=> %{prefix_key_1: :val_1, prefix_key_2: :val_2}
```
It seems to me that we already have good functionality for taking specific
keys out of a map by using Map.take/2
(which is effectively the same thing we are doing in the examples above)
but no good way of bulk updating specific key names.
My proposal would be to be able to pass a `prefix` as an option to
`Map.take` which would look roughly like the following:
```
Map.take(map, [:key_1, :key_2, :key_3], prefix: :prefix)
=> %{prefix_key_1: :val_1, prefix_key_2: :val_2, prefix_key_3: :val_3}
```
Pros:
* A simpler interface to take keys from a map and "rename" them according
to the context they will be used for
Cons:
* Using the `prefix` option would mean that all the keys would get
prefixed, a mixed approach would still require the examples showed above.
* Might make Map.take do too much at once
Since the Cons might be might seem to discourage this approach, another
proposal would be to introduce Map.prefix/2 and Map.suffix/2 which would
only
update the chosen keys in a map like so:
```
map
|> Map.take([:key_1, :key_2, :key_3, :key_4])
|> Map.prefix([:key_3, :key_4], :prefix)
=> %{key_1: :val_1, key_2: val_2, prefix_key_3: :val_3, prefix_key_4:
:val_4}
```
Interested in hearing your thoughts 😊
Thank you,
Tiago
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