This function returns the substring of the input string that precedes the first occurrence of the search string or the empty string if the input string does not contain the search string.

Signature:

substring-before(inputString as string,searchString as string)

Arguments:

• inputString: The input string.

• searchString: The string for which to search.

For example:

substring-before('1999/04/01','/') returns '1999'.