[Bug-apl] n wise reduction after 740

[Xiao-Yong Jin]

Hello,

It breaks when the left argument is 1.  In addition, with the internal macros, 
the si stack is polluted.

      1+/⍳5
1 2 3 4 5
      1{⍺+⍵}/⍳5
INDEX ERROR
μ-Z__pA_LO_REDUCE_X_B[5]  μ-T←⊂(⊃μ-B1[μ-H;μ-a-μ-M;μ-L])μ-LO⊃μ-T
                                 ^                         ^
      )sis
μ-Z__pA_LO_REDUCE_X_B[5]  μ-T←⊂(⊃μ-B1[μ-H;μ-a-μ-M;μ-L])μ-LO⊃μ-T
                                 ^                         ^
⋆  1{⍺+⍵}/⍳5
   ^

      )sinl
μ-Z__pA_LO_REDUCE_X_B[5]  μ-Z μ-A μ-LO μ-B μ-B1 μ-rho_Z μ-rho_B1 μ-T μ-H μ-M 
μ-L μ-a μ-N μ-I μ-I_max
⋆

Best,
Xiao-Yong