Why can't tuples in Scala be traversed? -

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suppose create tuple6: 

val tup = (true, 1 , "hello" , 0.4 , "world" , 0 ) tup: (boolean, int, string, float, string, int)

and can access elements of tuple using ._<position> tup._1 , tup._2 , on. why 

for (i <- 1 6)      println(tup._i)

give me error saying 

value _i not member of (string, int, boolean, string, double, int)

i understand stated tuples not iterable, if ._1 works , shouldn't ._i work same way ?

it boils down type.

what type dynamic accessor such _<position> have? in general case, valid 1 any. in strongly-typed language such scala useless purposes.

the news problem can handled in type-safe manner - see e.g. the hlist-style tuple handling in shapeless.

however, there no such mechanism available in standard scala library (barring heavy metaprogramming such macros).


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