scala - Creating a Class[T] from a Manifest[T] without casting -

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given ev: manifest[t] can class[t] using ev.erasure.asinstanceof[class[t]]. it's shame ev.erasure alone returns static type of class[_].

can class[t] manifest without casting? if not there reason why blessed scala creators have gone raw return type in erasure method?

i understand may have negligible impact on code i've run issue in arguably non-idiomatic piece of scala code , curious more else.

no, have cast — , should so. cast potentially unsafe, depending on want returned class instance. imagine want roll in own version of cast:

def cast[t](obj: any)(implicit m: manifest[t]) =   m.erasure.asinstanceof[class[t]].cast(obj)

this dangerous — indicated unchecked asinstanceof. why? because code runs fine such nonsense, instance:

val listint = list(1, 2, 3) val liststring = cast[list[string]](listint)

there, list[int] typed list[string]. , compiles , runs fine, you'll classcastexception later in code @ unexpected line. that's why cannot directly class[t] manifest[t] — because unsafe.


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