Trace (GenericNamedArraylist subroutine)
Trace displays the contents of a FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist in a readable form, useful for debugging, for example. Trace is identical to Print and Audit, except the result is sent to the selected Trace stream (like the User Language Trace statement).
anyNal:Trace[( [itemFunction], [NumWidth= number], [Separator= string], - [Start= number], [MaxItems= number], [Label= string], - [NameWidth= number])]
|anyNal||A FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist object.|
|itemFunction||The method that is to be applied to anyNal items to produce the printed output. The itemFunction method must take no parameters and produce an intrinsic (Float, String, or Unicode) value. It may be a system or user-written method, a class Variable or Property, a local method, or a method variable.
The default value of itemFunction is ToString.
|NumWidth||The number of bytes in the display of each item to use for the item number. This is an optional, name required, parameter.
Item numbers are right-justified within the indicated number of bytes, and they are truncated on the left if the length of the item number exceeds the space allocated for it. NumWidth must be a number between
If NumWidth is
|Separator||A string, 15 characters or less, to be used to separate both the item number and the item name from what follows. That is, the string you specify appears twice: once after the item number, and once after the item name.
This is an optional, name required, argument which defaults to a colon followed by a space (
|Start||The item number of the initial item in the output display. This is an optional, name required, argument which defaults to |
|MaxItems||The maximum number of items to display. A zero or negative value means to display all the items from Start to the end of the anyNal.
This is an optional, name required, argument which defaults to zero.
|Label||A string that gets output before each line. This is useful for "tagging" lines to make them more identifiable.
This is an optional, name required, argument which defaults to a null string.
|NameWidth||The number of bytes in the display of the item name. This must be a number from -1 through 255. This is an optional, name required, argument.
Item names are left-justified within the indicated number of bytes, and they are truncated on the right if the length of the item name exceeds the space allocated for it. For a UnicodeNamedArraylist, the items names are converted to EBCDIC (using character encoding for untranslatable characters). This can result in names being truncated in the middle of a character encoding, as shown in "Examples of subscript display format for named collections"
The default is
- All errors in Trace result in request cancellation.
To see what Trace displays are like, see the Print method calls in "Printing a collection".
- Audit and Print are the same as Trace except they send their output to the Model 204 audit trail or to the user's standard output destination, respectively.