## 孉T Object Attributes

The dyadic system function 孉T returns a variety of attributes for objects named in its right argument. The right argument should be a character scalar, vector or matrix of names and the left argument an integer in the range 1 - 4. The information available is:

                Left           Length of        Attributes Returned
              Argument          result
              挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝挝
                 1                3             Valences
                 2                7             Fix timestamp
                 3                4             Execution properties
                 4                2             Object size

and the attributes are defined as follows (using the sample workspace defined below):

                 )FNS                    (Sample workspace)
           GO      STOP    WAIT
                 )VARS
           NUMS

### Valences (Left argument 1)

The first element of the valence vector is 1 if the object is a variable or function with an explicit result and 0 for other cases. The second element is 0 1 for monadic functions, 2 for dyadic or nomadic functions, and 0 otherwise. The third element is 0 if the object is not an operator, 1 for monadic operators, 2 for dyadic operators.

                 (孨L 2 3),1 孉T 孨L 2 3
           GO   1 0 0                    (Niladic function, explicit result)
           NUMS 1 0 0                    (Variable)
           STOP 0 0 0                    (Niladic function, no result)
           WAIT 0 2 0                    (Dyadic/nomadic function, no result)

### Fix timestamp (Left argument 2)

If the named object is a function/operator, the timestamp of the latest fix of the function is returned.

                 (孨L 2 3),2 孉T 孨L 2 3
           GO   1990 5 25 0 19 14 703    (Latest fix time)
           NUMS    0 0  0 0  0  0   0    (Not a function)
           STOP 1990 5 25 0 19 10 906
           WAIT 1990 5 25 0 19 30 640

### Execution properties (Left argument 3)

A four element vector detailing the four execution properties:

           Nondisplayable; Nonsuspendable; Ignores weak interrupts; Converts APL
           errors to DOMAIN ERROR

Thus the vector is 0 0 0 0 for unlocked functions and 1 1 1 1 for locked functions.

                 (孨L 2 3),3 孉T 孨L 2 3
           GO   0 0 0 0
           NUMS 0 0 0 0
           STOP 0 0 0 0
           WAIT 0 0 0 0

### Object size (Left argument 4)

A two element vector is returned for each object named, showing first the size of the object as a whole, and secondly either size of the data portion (for variables) or repeating the object size.

                 (孨L 2 3),4 孉T 孨L 2 3
           GO   100 100                  (100 byte function)
           NUMS 56  40                   (56 byte variable, 40 byte data portion)
           STOP 68  68
           WAIT 104 104

Topic: APLX Help : Help on APL language : System Functions & Variables : 孉T Object Attributes

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