SAS 9.4 Macro Language, 5th Edition

Appendix 3

SAS Tokens

SAS Tokens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435

List of Tokens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435

SAS Tokens

When SAS processes a program, a component called the word scanner reads the

program, character by character, and groups the characters into words. These words are

referred to as tokens.

List of Tokens

SAS recognizes four general types of tokens:

Literal

One or more characters enclosed in single or double quotation marks. Examples of

literals include the following:

Table A3.1 Literals

'CARY' "2008"

'Dr. Kemple-Long' '<entry align="center">'

Name

One or more characters beginning with a letter or an underscore. Other characters

can be letters, underscores, and digits.

Table A3.2 Names

data _test linesleft

f25 univariate otherwise

435

year_2008 descending

Number

A numeric value. Number tokens include the following:

• integers. Integers are numbers that do not contain a decimal point or an exponent.

Examples of integers include 1, 72, and 5000. SAS date, time, and datetime

constants such as '24AUG2008'D are integers, as are hexadecimal constants such

as 0C4X.

• real (floating-point) numbers. Floating-point numbers contain a decimal point or

an exponent. Examples include numbers such as 2.35, 5., 2.3E1, and 5.4E− 1.

Special character

Any character that is not a letter, number, or underscore. The following characters

are some special characters:

= + − % & ; ( ) #

The maximum length of any type of token is 32,767 characters. A token ends when the

tokenizer encounters one of the following situations:

• the beginning of a new token.

• a blank after a name or number token.

• in a literal token, a quotation mark of the same type that started the token. There is an

exception. A quotation mark followed by a quotation mark of the same type is

interpreted as a single quotation mark that becomes part of the literal token. For

example, in 'Mary''s', the fourth quotation mark terminates the literal token. The

second and third quotation marks are interpreted as a single character, which is

included in the literal token.

436 Appendix 3 • SAS Tokens