Let's say I have the following:
val int_string = "Int"
I want to get a map. In the process of running the program, I need to infer its type from the data, and then create a map，like in spark dataframe
| key | count | key_radio | sample_radio |
|---|---|---|---|
| 1 | 2 | 0.2857142857142857 | 0.5 |
| 3 | 2 | 0.2857142857142857 | 0.5 |
| 2 | 3 | 0.42857142857142855 | 0.5 |
I only know the key column is “int”，but how can I create the Int object? from the string “Int”
Map[Int,Double] = ???
In val int_string = "Int" the string "Int" is a runtime thing.
In val m: Map[Int,Double] = ??? the type Int is a compile-time thing.
You can't have Int at compile time (i.e. earlier) based on information at runtime (i.e. later).
You should provide more details how you're going to use Map[Int,Double], why is Map[Any,Double] not enough etc.
Depending on your use case, Map[Any,Double] (or even Map[Any,Any]) could be enough or something else can be done or in rare cases, when Int is actually significant, one can use reflective toolbox (creating new compile time inside runtime)
tb.eval(tb.parse(s"val m: Map[$int_string,Double] = ???"))
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