pTAL Conversion Guide

pTAL Conversion Guide—527302-002
15-1
15 Statements
This section describes the differences between statements in TAL and pTAL.
Table 15-1 on page 15-1 lists briefly the changes in each statement.
Table 15-1. Summary of Statement Differences in pTAL (page 1 of 2)
Statement Differences From TAL
ASSERT No change.
Assignment Statement
on page 15-2 pTAL enforces strong typing.
CALL Statement
on page 15-7 The data types of formal and actual parameters
must match.
CASE Statement
on page 15-8 A program aborts if the case index does match any
alternative and the CASE statement does not
specify an OTHERWISE alternative. CASE
statements must have at least one alternative.
In pTAL, a CASE statement index or selector can be
an INT(32) expression.
CODE pTAL does not support CODE statements.
DO-UNTIL Statement
on page 15-11 Hardware indicators cannot appear in the
conditional expression of a DO-UNTIL statement.
DROP Statement
on page 15-12 The value in a USE variable is not available after
the USE variable is dropped.
GOTO Statement
on page 15-12 If a GOTO statement in a subprocedure references
a label in the containing procedure, the containing
procedure must declare the label in a LABEL
declaration.
GOTO statements cannot branch from a block in
which overflow trapping behavior is unspecified to a
block in which overflow trapping behavior is
specified.
IF Statement
on page 15-16 Numerous changes with respect to testing hardware
indicators.
Move Statement
on page 15-17 The keyword WORDS means 16 bits as it does in
TAL.
New built-in routines $FILL8, $FILL16, and
$FILL32, fill an array with repetitions of the same 8-
bit, 16-bit, or 32-bit data, respectively.