empty
Whether a value is the empty sequence
Description
The fn:empty function checks whether sequence is empty, meaning that it contains zero items. A sequence is not considered empty just because it only contains a zero-length string, the value 0, or an element with empty content.
It is often unnecessary to call the fn:empty function because sequences are automatically converted to their effective boolean value where a boolean value is expected
Parameters |
Description |
|---|---|
arg:string() |
Examples
XPath |
Results |
Explanation |
|---|---|---|
empty( (‘a’, ‘b’, ‘c’) ) |
false |
|
empty( () ) |
true |
|
empty(0) |
false |
|
empty($in-xml/a) |
false |
|
empty($in-xml/b) |
false |
|
empty($in-xml/c) |
false |
|
empty($in-xml/foo) |
true |
Or a static error, if static typing is in effect and foo is not an allowed child. |
XPath |
Results |
|---|---|
empty( (‘a’, ‘b’, ‘c’) ) |
false |
empty( () ) |
true |
empty(0) |
false |
empty($in-xml/a) |
false |
empty($in-xml/b) |
false |
empty($in-xml/c) |
false |
empty($in-xml/foo) |
true |