HLASM Language Reference

Data Attributes
The value of an attribute for a variable symbol specified in an attribute reference
comes from the value substituted for the variable symbol as follows:
SET Symbols and System Variable Symbols: For SET symbols and all system
variable symbols other than &SYSLIST, the attribute values come from the current
value of these symbols.
Symbolic Parameters and &SYSLIST: For symbolic parameters and the system
variable symbol, &SYSLIST, the values of the count and number attributes come
from the operands of macro instructions. The name field entry of the call is an
“operand,” and is referenceable as &SYSLIST(0). The values of the type, length,
scale, and integer attributes, however, come from the values represented by the
macro instruction operands, as follows:
1. If the operand is a sublist, the entire sublist and each entry of the sublist can
possess attributes; all the individual entries and the whole sublist have the
same attributes as those of the first suboperand in the sublist (except for the
count attribute, which can be different, and the number attribute which is
relevant only for the whole sublist).
2. If the first character or characters of the operand (or sublist entry) constitute an
ordinary symbol, and this symbol is followed by either an arithmetic operator (+,
−, *, or /), a left parenthesis, a comma, or a space, then the value of the
attributes for the operand are the same as for the ordinary symbol.
3. If the operand (or sublist entry) is a character string other than a sublist or the
character string described in the previous point, the type attribute is undefined
(U) and the length, scale, and integer attributes are invalid.
Because the count (K'), number (N'), and defined (D') attribute references are
allowed only in conditional assembly instructions, their values are available only
during conditional assembly processing. They are not available at ordinary
assembly time.
The system variable symbol &SYSLIST, with a valid subscript, can be used in an
attribute reference to refer to a macro instruction operand, and, in turn, to an
ordinary symbol. Thus, any of the attribute values for macro instruction operands
and ordinary symbols listed below can also be substituted for an attribute reference
containing &SYSLIST (see “&SYSLIST System Variable Symbol” on page 276).
Type Attribute (T')
The type attribute has a value of a single alphabetic character that shows the type
of data represented by:
An ordinary symbol
A macro instruction operand
A SET symbol
A literal
A system variable symbol
The type attribute can change during an assembly. The lookahead search might
assign one attribute, whereas the symbol table at the end of the assembly might
display another.
328 HLASM V1R5 Language Reference