pTAL Reference Manual (G06.24+, H06.09+, J06.03+)

Identifiers

Identifiers must conform to these rules:

• Identifiers can have up to 132 characters. You can limit the identifier to 31 characters by

setting the DO_TNS_SYNTAX (page 389).

• Identifiers begin with an alphabetic character, an underscore (_), or a circumflex (^).

• Identifiers contain alphabetic characters, numeric characters, underscores, or circumflexes.

• Identifiers contain lowercase and uppercase alphabetic characters. The compiler treats all

characters as uppercase.

• Identifiers cannot be reserved keywords (see Table 9 (page 37)).

• Identifiers can be nonreserved keywords, except as noted in Table 10 (page 37).

In addition to the preceding rules, HP recommends that you:

• Use underscores rather than circumflexes to separate words in identifiers (for example, use

Name_Using_Circumflexes rather than Name^Using^Circumflexes). This guideline

reflects international character-set standards, which allow the character printed for the circumflex

to vary by country.

• Do not end identifiers with an underscore. The trailing underscore is reserved for identifiers

supplied by the operating system (such as Name_Using_Trailing_Underscore_).

Example 1 Correct Identifiers

_2345678012_31_characters

name_with_exactly_31_characters

Example 2 Incorrect Identifiers

ProblemIdentifier

Begins with a number2abc

Contains % symbolab%99

Reserved wordVARIABLE

Each identifier belongs to an identifier class. The compiler determines the identifier class based

on how you declare the identifier.

Table 15 Identifier Classes

DescriptionClass

Global data blockBlock

Read only (P-relative) arrayCode

Simple variable, array, nonstructure pointer, structure pointer, structure, or structure

data item

Variable

Named textDEFINE*

Procedure or subprocedure that returns a valueFunction

Statement labelLabel

Named constantLITERAL

Procedure or subprocedure that does not return a valuePROC

42 Language Elements