You display the contents of a data structure or its subfields as you would
any standalone field. You simply use the data structure name after EVAL to
see the entire contents, or the subfield name to see a subset.
If the data structure is qualified, specify the subfields using
either of the following notations:
EVAL subfield-name OF datastructure-name
EVAL datastructure-name.subfield-name:
For example, to display subfield NAME of qualified data structure
INFO, type one of the following:
EVAL NAME OF INFO
EVAL NAME OF INFO EVAL INFO.NAME
When displaying a multiple-occurrence data structure, an EVAL on the data
structure name will show the subfields using the current index. To specify
a particular occurrence, specify the index in parentheses following the data
structure name. For example, to display the contents of the second occurrence
of DS1, type:
EVAL DS1(2)
Similarly, to view the contents of a particular occurrence of a subfield,
use the index notation.
To determine the value of the current index, enter the following command:
EVAL _QRNU_DSI_name
where name represents the
data structure name in question.
If a subfield is defined as an array overlay of another subfield, to see
the contents of the overlay subfield, you can use the %INDEX built-in function
to specify the occurrence, and the index notation to specify the array.
An alternative way of displaying a subfield which is an array overlay is
to use the following notation:
EVAL subfield-name(occurrence-index,array-index)
where the variable subfield-name is the name
of the subfield you wish to display, occurrence-index is
the number of the array occurrence to display, and array-index is the number of the element to display.
Figure 1 shows some examples of using EVAL with the the data
structures defined in DBGEX.
To display a data structure for which no subfields have been defined, you
must use the character display function of EVAL which is discussed below.