NVALID Function

Checks the validity of a character string for use as a SAS variable name.

Category:	Character
Restriction:	I18N Level 0 functions are designed for use with Single Byte Character Sets (SBCS) only.

Syntax

NVALID(string<,validvarname> )

Required Argument

string

specifies a character constant, variable, or expression which will be checked to determine whether its value can be used as a SAS variable name.

Note: Trailing blanks are ignored.

Tip	Enclose a literal string of characters in quotation marks.

Optional Argument

validvarname

is a character constant, variable, or expression that specifies one of the following values:

V7

determines that string is a valid SAS variable name when all three of the following are true:

string begins with an English letter or an underscore
All subsequent characters are English letters, underscores, or digits
The length is 32 or fewer alphanumeric characters

ANY

determines that string is a valid SAS variable name if it contains 32 or fewer characters of any type, including blanks.

NLITERAL

determines that string is a valid SAS variable name if it is in the form of a SAS name literal ('name'N) or if it is a valid SAS variable name when VALIDVARNAME=V7.

See	V7 above in this same list.

Default

If no value is specified, the NVALID function determines that string is a valid SAS variable name based on the value of the SAS system option VALIDVARNAME=.

Details

The NVALID function checks the value of string to determine whether it can be used as a SAS variable name.

The NVALID function returns a value of 1 or 0.

Condition		Returned Value
string can be used as a SAS variable name		1
string cannot be used as a SAS variable name		0

Example

This example determines the validity of specified strings as SAS variable names. The value that is returned by the NVALID function varies with the validvarname argument. The value of 1 is returned when the string is determined to be a valid SAS variable name under the rules for the specified validvarname argument. Otherwise, the value of 0 is returned.

options validvarname=v7 ls=64;
data string;
   input string $char40.;
   v7=nvalid(string,'v7');
   any=nvalid(string,'any');
   nliteral=nvalid(string,'nliteral');
   default=nvalid(string);
   datalines;
Tooooooooooooooooooooooooooo Long
OK
Very_Long_But_Still_OK_for_V7
1st_char_is_a_digit
Embedded blank
!@#$%^&*
"Very Loooong N-Literal with """N
'No closing quotation mark
;
          
proc print noobs;
title1 'NLITERAL and Validvarname Arguments Determine';
title2 'Invalid (0) and Valid (1) SAS Variable Names';
run;

Determining the Validity of SAS Variable Names with NLITERAL