FIELD Verb
Syntax
FIELD strname,str{,[int]}=expr{,ERR=lineref}
Description
For BBj-specific documentation, see Field Verb - BBj.
The FIELD verb allows assignment of data into fields of a string template.
|
Parameter |
Description |
|---|---|
|
strname |
Simple string variable dimensioned with a template. An !ERROR=47 is generated when str does not appear in strname. |
|
str |
Field name within the template. |
|
int |
Index of the array specified by str. |
|
ERR=lineref |
Branch to be taken if an error occurs during execution. |
For additional information, see String Templates in the User's Reference Guide. Though hard-coded field names may be used, the FIELD verb allows dynamic run-time access to fields. For example, the following statement is hard coded:
LET A.FIELD$="data"
The same thing can be done with the FIELD statement:
FIELD A$,"FIELD"="data"
The advantage of the FIELD statement is that it does not have to be hard coded. The following example does the same thing:
LET B$="FIELD"
FIELD A$,B$="data"
This can be used for database and report generator applications that may access data dictionaries at run time.
Numeric data may also be assigned:
FIELD A$,"TOTAL"=X*4.5
The use of a numeric expression instead of a string expression generates an error, if the field called "TOTAL" was not defined as numeric.
For repeating fields, a subscript could be provided:
FIELD A$,"RATE",[10]=2.5
The brackets are required to avoid syntax ambiguity. The value, 10, indicates the tenth value of the field called RATE and assumes that RATE was defined as a repeating field.