# op:add-yearMonthDurations

Adds $yearMonthDuration-var1 to $yearMonthDuration-var2.

### Signatures

op:add-yearMonthDurations(xf:yearMonthDuration $yearMonthDuration-var1, xf:yearMonthDuration $yearMonthDuration-var2) —> xf:yearMonthDuration

### Arguments

Data Type | Argument | Description
--- | --- | ---
xf:yearMonthDuration | $yearMonthDuration-var1 | Contains a time duration that can contain years and months.
xf:yearMonthDuration | $yearMonthDuration-var2 | Contains a time duration that can contain years and months.

### Returns

Returns the yearMonthDuration value of adding $yearMonthDuration-var1 to $yearMonthDuration-var2.

### Examples

#### Simple

The following example query adds a yearMonthDuration value equal to 1 year and 2 months to a yearMonthDuration value equal to 2 years and 11 months as shown in the following query:

    <yearMonthDuration>{
    	op:add-yearMonthDurations(xf:yearMonthDuration("P1Y2M"), xf:yearMonthDuration("P2Y11M"))
    }</yearMonthDuration>

The resulting yearMonthDuration value of 4 years and 1 month is returned as shown in the following result:

    <yearMonthDuration>P4Y1M</yearMonthDuration>

Related Topics

W3C add-yearMonthDurations operator description.

W3C yearMonthDuration description.

xf:yearMonthDuration constructor description.