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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