One-dimensional index arrays

Uses
- One-dimensional arrays
- Integers

An index array of length n contains the integers from 1 to n. It is defined by the operator
 IndexArray(ℕ.nz) : Array1D(ℕ.nz)
 IndexArray(zero) : EmptyArray(0)

The array is constructed by Pharo code:
 IndexArray(n:ℕ) ⇒ Pharo:"n ensureNumber. n signature indexArrayTerm: n"

Example

An index array of length 5: IndexArray(5) ⇒ {[1, 2, 3, 4, 5]}