ISDATE

The ISDATE program determines whether a text expression represents a valid date. ISDATE acts as a BOOLEAN function, returning YES when the text expression does represent a valid date and NO when it does not. ISDATE does not convert the text expression to a DATE formula. ISDATE only tests a text expression to see if it can be converted to a DATE value. You must use CONVERT to make the conversion.

Return Value

BOOLEAN

Syntax

ISDATE(test-date)

Arguments

test-date: A single-line ID or TEXT expression to be examined to see if it represents a valid date, as defined by the DATE data type.

Notes

Valid Date Styles

For a description of the valid styles for entering dates, see DATEORDER.

Examples

Example 15-21 Testing a Text Expression

In the following statement, the ISDATE program tests a literal text expression to see if it is a valid date, and the output is sent to the current outfile.

SHOW ISDATE('3 5 1995')

This statement produces the following output.

YES