# xf:count

Counts the number items in the sequence.

### Signatures

xf:count(item* $item-var) —> xs:unsignedInt

### Arguments

Data Type | Argument | Description
--- | --- | ---
item* | $item-var | Represents the sequence to be counted.

### Returns

Returns the number of items in a sequence passed into $item-var as an unsignedInt value.

Returns 0 if $item-var is the empty sequence. The empty sequence is a sequence containing zero items (), which is similar to null in SQL.

### Examples

#### Simple

Invoking count(("a","b","c")) returns the unsigned integer value of 3, as shown in the following example query:

    <result>{xf:count(("a","b","c"))}</result>

The preceding query generates the following result:

    <result>3</result>

#### Empty Sequence

Invoking count(()) returns the unsigned integer value of 0 because () is an empty sequence (contains no elements), as shown in the following example query:

    <result>{xf:count(())}</result>

The preceding query generates the following result:

    <result>0</result>

Related Topics

W3C count function description.