SAS Component Language Dictionary

_BLANK_

Special missing value

Category:

System Variable

Details
Example
See Also

Details

_BLANK_ is a system variable that is created for every SCL program that you compile. The compiler creates a space for _BLANK_ in the SCL data vector. In SAS/AF applications, you can compare the value of window variables against the value _BLANK_ to test whether a value has been entered in a field in the window. The test is valid for both numeric and character variables. You can also use _BLANK_ in assignment statements to reset a window variable to a blank, as if the user had not entered a value in the field. You cannot reset the value of the _BLANK_ variable itself.

In comparison operations, _BLANK_ is considered the smallest missing value.

Example

The following code fragment prints a message if X is modified and is blank:

if modified(x) and x eq _blank_ then
   _msg_ = 'Please enter a value';