pTAL Conversion Guide

pTAL Conversion Guide—527302-002

6-1

Constants, LITERALs, and DEFINEs

Character constants are the same in TAL and pTAL except in null strings and REAL

variables.

Null Strings

TAL

You can assign a character constant null string ("") to a variable in the variable’s

declaration or in an assignment statement. You cannot, however, declare a LITERAL

whose value is a null string; therefore, you cannot initialize a variable to a null string

using a LITERAL.

pTAL

You cannot assign a null string to a variable in the variable’s declaration or in an

assignment statement:

INT i := ""; ! Valid in TAL, invalid in pTAL

i := ""; ! Valid in TAL, invalid in pTAL

REAL Variables

TAL

You can store a character constant in a REAL variable in the variable’s declaration or

in an assignment statement.

pTAL

You cannot assign a character constant to a REAL variable in an assignment

statement:

REAL s;

s := "ABCD"; ! Valid in TAL, invalid in pTAL