Compaq AA-PWCBD-TE Lexical Elements of the DEC Text Processing Utility Language

4
Lexical Elements of the DEC Text Processing
Utility Language
4.1 Overview
A DECTPU program is composed of lexical elements. A lexical element may be
an individual character, such as an arithmetic operator, or itmay be a group of
characters, such as an identifier. The basic unit of a lexical element is a character
from either the DEC Multinational Character Set or the ISO_LATIN1 Character
Set.
This chapter describes the following DECTPU lexical elements:
• Character set
• Identifiers
• Variables
• Constants
• Operators
• Expressions
• Reserved words
• Lexical keywords
4.2 Case Sensitivity of Characters
The DECTPU compiler does not distinguish between uppercase and lowercase
characters except when they appear as part of a quoted string. For example, the
word EDITOR has the same meaning when written in any of the following ways:
EDITOR
EDitOR
editor
The following, however, are quoted strings, and therefore represent different
values:
"XYZ"
"xyz"
Lexical Elements of the DEC Text Processing Utility Language 4–1