Canonical Representation R←⎕CR Y

Y must be a simple character scalar or vector which represents the name of a defined function or operator.

If Y is a name of a defined function or operator, R is a simple character matrix. The first row of R is the function or operator header. Subsequent rows are lines of the function or operator. R contains no unnecessary blanks, except for leading indentation of control structures, trailing blanks that pad each row, and the blanks in comments. If Y is the name of a variable, a locked function or operator, an external function, or is undefined, R is an empty matrix whose shape is 0 0.

Example

      ∇R←MEAN X    ⍝ Arithmetic mean
[1]  R←(+/X)÷⍴X
[2]  ∇
      +F←⎕CR'MEAN'
R←MEAN X    ⍝ Arithmetic mean
R←(+/X)÷⍴X

      ⍴F
2 30

The definition of ⎕CR has been extended to names assigned to functions by specification (←), and to local names of functions used as operands to defined operators.

If Y is a name assigned to a primitive function, R is a one-element vector containing the corresponding function symbol. If Y is a name assigned to a system function, R is a one element nested array containing the name of the system function.

Examples

      PLUS←+
      +F←⎕CR'PLUS'
+
      ⍴F
1
      C←⎕CR
      C'C'
 ⎕CR
      ⍴C'C'
1

      ∇R←CONDITION (FN1 ELSE FN2) X
[1]   →CONDITION/L1
[2]   R←FN2 X ⋄ →0
[3]  L1:R←FN1 X
[4]   ∇

      2 ⎕STOP 'ELSE'
      (X≥0) ⌊ ELSE ⌈ X←¯2.5

ELSE[2]
       X
¯2.5
       ⎕CR'FN2'
⌈
       →⎕LC
¯2

If Y is a name assigned to a derived function, R is a vector whose elements represent the arrays, functions, and operators from which Y was constructed. Constituent functions are represented by their own ⎕CRs, so in this respect the definition of ⎕CR is recursive. Primitive operators are treated like primitive functions, and are represented by their corresponding symbols. Arrays are represented by themselves.

Example

      BOX←2 2∘⍴
      +F←⎕CR'BOX'
 2 2 ∘⍴
      ⍴F
3
      ]display F
.→----------.
| .→--.     |
| |2 2| ∘ ⍴ |
| '~--' - - |
'∊----------'

If Y is a name assigned to a defined function, R is the ⎕CR of the defined function. In particular, the name that appears in the function header is the name of the original defined function, not the assigned name Y.

Example

      AVERAGE←MEAN
      ⎕CR'AVERAGE'
R←MEAN X    ⍝ Arithmetic mean
R←(+/X)÷⍴X