[Bug-apl] Scan operator has strange behaviour

[Elias Mårtenson]

The following code returns the expected results:

      {⍺+⍵}\⍳10

1 3 6 10 15 21 28 36 45 55

However, if I also print all the calls, I get a lot more evaluations of the function than expected:

      {(⍺+⍵)⊣⎕←('[',(⍕⍺),',',(⍕⍵),']')}\⍳10

[1,2]

[2,3]

[1,5]

[3,4]

[2,7]

[1,9]

[4,5]

[3,9]

[2,12]

[1,14]

[5,6]

[4,11]

[3,15]

[2,18]

[1,20]

[6,7]

[5,13]

[4,18]

[3,22]

[2,25]

[1,27]

[7,8]

[6,15]

[5,21]

[4,26]

[3,30]

[2,33]

[1,35]

[8,9]

[7,17]

[6,24]

[5,30]

[4,35]

[3,39]

[2,42]

[1,44]

[9,10]

[8,19]

[7,27]

[6,34]

[5,40]

[4,45]

[3,49]

[2,52]

[1,54]

1 3 6 10 15 21 28 36 45 55

This can't possibly be correct?

Regards,

Elias