Returns characters before the first occurrence of specific string in text. Parameter string must not be empty. This function is case-sensitive.
|keepbefore( '5pm', 'pm' )||'5'|
|keepbefore('October 2015','2015')||'October '|
The functions can have the optional third parameter with the index of the separator. The index can be negative - in this case, it's counted from the end of the text.
|keepbefore( 'a/b/c/d', '/', 2)||'a/b'|
|keepbefore( 'a/b/c/d', '/', -1)||'a/b/c'|