Add experimental NamedTuple copyFrom method #23135
Conversation
`copyFrom` chosen as it has a slight difference i.e. the argument should be surrounded in extra parentheses. Also, it can not be used for target typing of fields.
|
rebased |
|
|
||
| @main def Test = | ||
| val foo: Foo = (name = "foo", mod = "some_mod") | ||
| val foo_updated: Foo = foo.copyFrom((mod = "bar")) // error, stays as String |
There was a problem hiding this comment.
here is a demo of the limitation of no target typing, which I guess could be mitigated with a dedicated feature, or a secondary library solution based on lenses
|
For reference, with the help you provided, I got this working in my code, including in an optimized form for the special-cased tuple sizes (up to 22): https://github.com/Ichoran/kse3/blob/fef8e9b971861306c5da30f12d868294f53b410f/basics/src/Labels.scala#L447-L466 It seems to work pretty well. If you want to not allow type changes, I'm sure one could do that type computation too--you're already matching the types of the labels, after all. (I did lenses too, but I didn't see much use for restricting types, so I didn't bother putting that into them, just regular map, delete, insert, etc.. Lensing by name-as-a-string-constant is kind of a neat trick. One doesn't even need macros at this point!) |
copyFromchosen as it has a slight difference i.e. the argument should be surrounded in extra parentheses. Also, it can not be used for target typing of fields.