pTAL Reference Manual (H06.03+)

Data Representation
HP pTAL Reference Manual—523746-005
3-9
Using Indexes to Access Array Elements
Using Indexes to Access Array Elements
Indexing produces the correct result for all data types including structures. Use
indexing wherever possible to adjust pointers.
Table 3-5. Valid Address Conversions
TO
FROM
B
A
D
D
R
W
A
D
D
R
C
B
A
D
D
R
C
W
A
D
D
R
S
G
B
A
D
D
R
S
G
X
B
A
D
D
R
S
G
W
A
D
D
R
S
G
X
W
A
D
D
R
E
X
T
A
D
D
R
P
R
O
C
A
D
D
RINTINT(32)
BADDR = R R R
WADDR R = R R
CBADDR =
CWADDR =
SGBADDR = = R R I
SGXBADDR = = R R I
SGWADDR R R = = I
SGXWADDR R R = = I
EXTADDR RREERRRR= I
PROCADDR =
INT IIII = E
INT(32) I E =
Key to Symbols = Same type, conversion unnecessary
V Valid
I Implicit conversion for assignments, actual parameters (passed either by value
or by reference), and RETURN statements
R Implicit conversion for parameters passed by reference, explicit conversion
required in other contexts
E Explicit conversion required (see Address-Conversion Routines
on page 15-14)
Blank Unsupported and illegal
Example 3-2. Using Indexing to Access an Array Element
int .p;
@p := @p[2] ! This statement is equivalent to
@p := @p '+' 4; ! this statement