Right Shoe
Monadic Right Shoe means

If ⎕ML<2Disclose;First

      ⊃ 'Word'
W
      ⊃ (1 2)(3 4 5)
1 2

If ⎕ML≥2Mix

      ⊃ (2 2)(3 3 3)
2 2 0
3 3 3
Dyadic Right Shoe means

Pick

      3 ⊃ 'Word'
r
      2 ⊃ (1 2)(3 4 5)
3 4 5

      2 1 ⊃ (1 2)(3 4 5)
3

Language Elements