pTAL Reference Manual (H06.08+)

Expressions
HP pTAL Reference Manual—523746-006
5-12
Extended Addresses
Extended Addresses
The following rules apply when you compare extended addresses (EXTADDRs):
•
Use signed relational operators to compare extended addresses. Unsigned
operators are not valid.
•
If you compare an extended address to a constant, the constant must be a 32-bit
integer.
Nonextended Addresses
The following rules apply when you compare nonextended addresses:
•
Use unsigned relational operators ( '<', '=', '>', '<=', '<>', '>='), a signed equality
operator (=), or a signed inequality operator (<>) to compare nonextended
addresses. The signed and unsigned equality operators produce the same results.
Similarly, the signed and unsigned inequality operators produce the same results.
•
Do not compare nonextended addresses using signed operators that test for
greater than or less than (<, <=, >, >=).
Valid comparisons:
INT .p, .q;
IF @p = 0 THEN ...
IF @p <> 0 THEN ...
IF @p = @q THEN ...
Both operands must have the same address type:
STRING .s;
BADDR .b;
IF @s = b THEN ... ! OK: @s is BADDR, b is BADDR
IF @s = @b THEN ... ! ERROR: @s is BADDR, @b is WADDR
Example 5-1. Extended Addresses
EXTADDR e;
INT .EXT i;
IF e < @i THEN ... ! OK: e and @i are both EXTADDR
IF @i >= 0D THEN ... ! OK: @i is EXTADDR, 0D is 32 bits
IF e = 0D THEN ... ! OK
IF e <> 0D THEN ... ! OK
IF e THEN ... ! OK
IF NOT e THEN ... ! OK
IF e > i THEN ... ! ERROR: e is EXTADDR, i is INT
IF e '<' @i THEN ... ! ERROR: Unsigned operators are not valid
! with EXTADDRs