cmp with Over operator

cmpOver.dyalog

cmp←{  ⍝ compare basic arrays, results in ¯1 (⍺ precedes ⍵), 0 (⍺ is identical to ⍵), or 1 (⍺ follows ⍵)

⍝ DEFINITION:
⍝            ┌
⍝            │ ¯1 if ⍺ strictly precedes ⍵
⍝ ⍺ cmp ⍵  = │  0 if ⍺ exactly matches   ⍵
⍝            │  1 if ⍺ strictly follows  ⍵
⍝            └

⍝ AXIOMS:
⍝ 1. exact comparisons, ⎕UCS for characters
⍝ 2. result is first non-zero in ravel order
⍝ 3. complex numbers have imaginary part as additional dimension after real part
⍝ 4. numbers precede characters
⍝ 5. dictionary order: "nothing precedes something", break ties by comparing shape
⍝ 6. visual fidelity: extend with leading 1-axes, break ties by comparing rank

     Ö←{(⍵⍵ ⍺)⍺⍺(⍵⍵ ⍵)}               ⍝ Over operator

     ⎕CT←⎕DCT←0 ⋄ ⎕FR←1287            ⍝ Axiom 1: exact or as exact as possible

     ⍺{11::0 ⋄ ⍺≡⍵}⍵:0                ⍝ Definition: exact match (trap DECF vs xomplex)

     ⍺>Ö(0∊⍴)⍵:¯1                     ⍝ Axiom 5: nothing before something
     ⍺<Ö(0∊⍴)⍵:1                      ⍝          something after nothing

     ⍺≢Ö(⍴⍴)⍵:c+(⍺ ∇ Ö(⍴⍴)⍵)×0=c←⍺ ∇ Ö(⊢⍴⍨⍴,⍨1⍴⍨r-(⍴⍴))⍵⊣r←⍺⌈Ö(⍴⍴)⍵ ⍝ Axiom 6: extend rank, compare, tie-break by rank

     ⍺≢Ö⍴⍵:c+(⍺ ∇ Ö(⌽⍴)⍵)×0=c←(⍺ ∇ Ö(m∘↑)⍵)⊣m←⍺⌊Ö⍴⍵ ⍝ Axiom 5: chop shape, compare, tie-break by shape

     t←⍺,Ö{(326≠t)×2-2|t←⎕DR ⍵}⍵      ⍝ Axiom 4: 1=num; 2=char; 0=other
     1 2≡t:¯1                         ⍝          num vs char
     2 1≡t:1                          ⍝          char vs num

     1 1≡t:⊃0~⍨,⍺(>-<)Ö(9 11∘○⍤1 0)⍵  ⍝ Axioms 3 & 2: first nonzero value of num vs num with catenated Zs
     2 2≡t:⊃0~⍨,⍺(>-<)Ö ⎕UCS ⍵        ⍝ Axioms 1 & 2: first nonzero value of char vs char using ⎕UCS

     |c←⍺ ∇ Ö⊃⍵:c ⋄ ⍺ ∇ Ö(1↓,)⍵       ⍝ Axiom 2: first non-zero in ravel order (for non-simple arrays)
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