broadcasting element-wise operation without materializing the data into Array?

[johnnychen94]

A = IndirectArray(rand(1:5, 64, 64), rand(1:10, 5))
float.(A) # what's needed to make this still an IndirectArray?

# internally, I'd like to make it work equivalently to
_float(A::IndirectArray) = IndirectArray(A.index, float.(A.values))

[timholy]

Since broadcasting acts on values only, I think (?) we could create custom copy!(::Broadcastable) methods for IndirectArray.