System Function AT

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Z←L ⎕AT R returns the attributes of the objects named in R.
R is a character scalar, vector, or matrix consisting of the names of objects (e.g., variables, functions, or operators).
L is an integer scalar whose value is either 1, 2, 3, 4, or 10.
Z is an integer vector or matrix.

If R is a scalar, it is treated as the name; if R is a vector, it is treated as a vector of names separated from one another by one or more blanks; if R is a matrix, each row is treated as a single name surrounded by zero or more blanks.

If R consists of a single name or L is 10, Z is a vector; otherwise Z is a matrix with as many rows as there are names in R.

The number of columns in Z depends upon the value of L.

  • If L is 1, the result describes the Valences of the objects named in R and has three columns consisting of
    [1] Whether or not there is an Explicit result (1 or 0): This value is 1 for variables and for functions/operators that return a result; 0 otherwise.
    [2] The Function Valence (0, 1, or 2): This value is 0 for a non-function or for a niladic function, 1 for a monadic function or for a monadic derived function from an operator, and 2 for a dyadic or ambivalent function or for a dyadic or ambivalent derived function from an operator.
    [3] The Operator valence (0, 1, or 2): This value is 0 for a non-operator, 1 for a monadic operator, and 2 for a dyadic operator.

  • If L is 2, the result describes the Fix Time of the objects named in R and has seven columns consisting of
    [1] Year
    [2] Month
    [3] Day
    [4] Hour
    [5] Minute
    [6] Second
    [7] Millisecond

    If an object named in R is not a user-defined function/operator, the corresponding row in the result is all 0. All times are in UTC and represent the time the function was last modified.

  • If L is 3, the result describes the Execution Properties of the objects named in R and has four columns consisting of
    [1] Whether or not the object is Nondisplayable (1 or 0)
    [2] Whether or not the object is Nonsuspendable (1 or 0)
    [3] Whether or not the object Ignores weak interrupts, i.e. Ctrl-C or Ctrl-Break (1 or 0)
    [4] Whether or not the object Converts non-resource errors to DOMAIN ERRORs (this value is always 0)

    If an object named in R is a variable, the corresponding row in the result is all 0. If an object named in R is a primitive or system function, the corresponding row in the result is 1 1 1 0. If an object named in R is a function array, train, or magic function, the corresponding row in the result is 0 1 1 0.

  • If L is 4, the result describes the Object Size of the objects named in R and has two columns consisting of
    [1] The object's size consisting of the object header and data sizes
    [2] The object's data size only.

  • If L is 10, the result describes the Function Type of the objects named in R. The values in the result are integer scalars one per name in R and have the following meaning:

    0 The object is not a function/operator
    1 The object is a Primitive Function or Operator f←+ f←/
    2 The object is a Derived Function or Operator f←+/ f←⍨∘÷
    3 The object is a User-defined Function or Operator ∇f ∇(LO f) R
    4 The object is a System Function or Operator f←⎕NL
    5 The object is an Anonymous Function or Operator f←{⍺+⍵} f←{⍺⍺/¨⍵}
    6 The object is a Train f←(+/÷≢)
    7 The object is a Name-Associated Function Not as yet implemented
    8 The object is a Java-Associated Function Not as yet implemented

Examples

⎕AT - Quad AT - Object Summary Attributes - sample dyadic calls (re workspace user-function attributes): 

      2 ⎕AT ⊃'UCase' 'LCase'  ⍝ Request to show 'Date/Time last modified' Attribute for two workspace functions
2015 2 4 0 23 55 926          ⍝ Yr Mo Day Hr Min Sec Milli-Secs format - same format as ⎕TS (quad time stamp)
2015 2 4 0 23 37 839
      X←⊃'UCase' 'LCase'
      ⍴X
2 5
      X
UCase
LCase
      (1 ⎕AT X),'|',(2 ⎕AT X),'|',(3 ⎕AT X),'|',(4 ⎕AT X),'|',(10 ⎕AT X)
1 1 0 | 2015 2 4 0 23 55 926 | 0 0 0 0 | 19626 6434 | 3
1 1 0 | 2015 2 4 0 23 37 839 | 0 0 0 0 | 18424 6448 | 3

⍝  1 1 0 = {Yes Explicit Function Result Z} {Monadic Function Valence} {Non-Operator}                    :  1 ⎕AT fcn-names
⍝  UTC/GMT Date/Time last edited-saved                                                                   :  2 ⎕AT fcn-names
⍝  0 0 0 0 = {Non-displayable (0), Non-suspendable (0), Ignores weak interrupts (0), Always zero (0)}    :  3 ⎕AT fcn-names
⍝  19626 6434 = {object header and data sizes, # bytes} {data size only, # bytes}                        :  4 ⎕AT fcn-names
⍝  3 = {Function Type = User-defined Function/operator}                                                  : 10 ⎕AT fcn-names

⍝  BE ADVISED: 2 ⎕AT for each object will be in UTC/GMT time (ditto ⎕VR) while ⎕TS will be in local time (e.g. Eastern or Pacific time),
⍝  so for comparisons between (2 ⎕AT functions v. ⎕TS) you have to add or subtract n hours from one or the other for equivalency!

See Also: Quad Time Stamp ⎕TS for 7-element DateTime stamp format.


Note: ⎕AT is a dyadic form system function, you cannot assign a value to it.

System Variables (A value may be assigned to these except for ⎕DM)
⎕ALX ⎕CT ⎕DM ⎕DT ⎕ELX ⎕FC ⎕FEATURE ⎕FPC ⎕IC ⎕IO
⎕LR ⎕LX ⎕PP ⎕PR ⎕PW ⎕RL ⎕SA ⎕WSID
Niladic System Functions (a value cannot be assigned to these)
⎕A ⎕AV ⎕EM ⎕ET ⎕LC ⎕NNAMES ⎕NNUMS ⎕SI ⎕SYSID ⎕SYSVER
⎕T ⎕TC ⎕TCBEL ⎕TCBS ⎕TCESC ⎕TCFF ⎕TCHT ⎕TCLF ⎕TCNL ⎕TCNUL
⎕TS ⎕WA
Monadic or dyadic system functions (a value cannot be assigned to these)
⎕AT ⎕CR ⎕DC ⎕DFT ⎕DL ⎕DR ⎕EA ⎕EC ⎕ERROR ⎕ES
⎕EX ⎕FMT ⎕FX ⎕MF ⎕NAPPEND ⎕NC ⎕NCREATE ⎕NERASE ⎕NINFO ⎕NL
⎕NLOCK ⎕NREAD ⎕NRENAME ⎕NREPLACE ⎕NRESIZE ⎕NSIZE ⎕NTIE ⎕NUNTIE ⎕STOP ⎕TF
⎕TRACE ⎕UCS ⎕VR
Note that quad functions and variables (except for the ⎕A family of functions) are case insensitive


See Also
System Commands System Variables and Functions Operators


Keyboard
Alt+Shift ⍪ ≡ ≢ ⍒ ⍋ ⌽ ⍉ ⊖ ⍟ ⍱ ⍲ ⍠ ⌹
Alt ⋄ ¨ ¯ < ≤ ∅ ≥ > ≠ ∨ ∧ × ÷
Shift ~ ! @ # $ % ^ & * ( ) _ +
Key ` 1 2 3 4 5 6 7 8 9 0 - =
Alt+Shift ⍷ √ ⍨ ⍸ ⍥ ⍣ ⍞ ⍬ ⊣
Alt ? ⍵ ∊ ⍴ § ↑ ↓ ⍳ ○ π ← → ⊢
Shift Q W E R T Y U I O P { } |
Key q w e r t y u i o p [ ] \
Alt+Shift ∫ ∂ ⌻ ⍢ ⍙ ⍤ ⍫ ⌷
Alt ⍺ ⌈ ⌊ ∞ ∇ ∆ ∘ ‼ ⎕ ⍎ ⍕
Shift A S D F G H J K L : "
Key a s d f g h j k l ; '
Alt+Shift ⊆ ⊇ χ ⍡ ⍭ ⊙
Alt ⊂ ⊃ ∩ ∪ ⊥ ⊤ ⍦ ⍝ ⍀ ⌿
Shift Z X C V B N M < > ?
Key z x c v b n m , . /
NARS 2000 Lang
Tool
Bar 		← → + - × ÷ * ⍟ ⌹ ○ ! ? √ | ⌈ ⌊ ⊥ ⊤ ⊣ ⊢
≡ ≢ < ≤ = ≥ > ≠ ∨ ∧ ⍱ ⍲ ↑ ↓ ⊂ ⊃ ⌷ ⍋ ⍒
⍳ ∊ ⍸ ⍷ ∪ ∩ ⊆ ⊇ ~ § π .. , ⍪ ⍴ ⌽ ⊖ ⍉
/ \ ⌿ ⍀ ⊙ ¨ ⍨ ⍤ ⍣ ⍡ ⍥ ⍦ . ∘ ⍠ ‼ ⌻ ∂ ∫ ⍞ ⎕ ⍎ ⍕
⋄ ⍝ ∇ ∆ ⍙ _ ⍺ ⍵ ¯ ⍬ ∞ ∅
Second Row i j k i j k l g p r v x

[[Category:Dyadic p[erators]]

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