Beside

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Beside (), Compose or After is a primitive operator. It shares the glyph with Bind. Called dyadically with function operands f and g, it uses g monadically to pre-processes the right argument before applying f to the given left argument and pre-processed right argument. Called monadically with operands f and g, it applies f to the result of applying g to the argument.

In usage, X fg Y is equivalent to X f g Y, and fg Y is equivalent to f g Y. Thus, beside can be defined as the dop { ⍺⍺ ⍵⍵ }.

Examples

When used monadically, fg behaves the same as an atop:

      -÷ 2 
¯0.5
      ⍝ same as
      -(÷2)
¯0.5

When used dyadically, fg forms a dyadic hook:

      'oy''yo'
1
      ⍝ same as
      'oy'≡⌽'yo'
1

When used monadically with Commute, fg forms a monadic hook:

      'UwU'
1
      ⍝ same as this, because operators are left-associative, unlike functions which are right-associative
      ()'UwU'
1
      ⍝ same as
      'UwU'≡⌽'UwU'
1

External links

Lessons

Documentation


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