8.2.2. Durations

Durations are used to calculate a value for end when one is not supplied to in_range operations. They contain the same fields as date_spec objects but without the limitations (ie. you can have a duration of 19 days). Like date_specs, any field not supplied is ignored.

8.2.2.1. Sample Time Based Expressions

Example 8.1. True if now is any time in the year 2005


  <rule id="rule1">
   <date_expression id="date_expr1" start="2005-001" operation="in_range">
    <duration years="1"/>
   </date_expression>
  </rule>

Example 8.2. Equivalent expression.


  <rule id="rule2">
   <date_expression id="date_expr2" operation="date_spec">
    <date_spec years="2005"/>
   </date_expression>
  </rule>

Example 8.3. 9am-5pm, Mon-Friday


  <rule id="rule3">
   <date_expression id="date_expr3" operation="date_spec">
    <date_spec hours="9-16" days="1-5"/>
   </date_expression>
  </rule>

Example 8.4. 9am-6pm, Mon-Friday, or all day saturday


  <rule id="rule4" boolean_op="or">
   <date_expression id="date_expr4-1" operation="date_spec">
    <date_spec hours="9-16" days="1-5"/>
   </date_expression>
   <date_expression id="date_expr4-2" operation="date_spec">
    <date_spec days="6"/>
   </date_expression>
  </rule>

Example 8.5. 9am-5pm or 9pm-12pm, Mon-Friday


  <rule id="rule5" boolean_op="and">
   <rule id="rule5-nested1" boolean_op="or">
    <date_expression id="date_expr5-1" operation="date_spec">
     <date_spec hours="9-16"/>
    </date_expression>
    <date_expression id="date_expr5-2" operation="date_spec">
     <date_spec hours="21-23"/>
    </date_expression>
   </rule>
   <date_expression id="date_expr5-3" operation="date_spec">
    <date_spec days="1-5"/>
   </date_expression>
  </rule>

Example 8.6. Mondays in March 2005


  <rule id="rule6" boolean_op="and">
   <date_expression id="date_expr6-1" operation="date_spec">
    <date_spec weekdays="1"/>
   </date_expression>
   <date_expression id="date_expr6-2" operation="in_range" start="2005-03-01" end="2005-04-01"/>
  </rule>

NOTE: Because no time is specified, 00:00:00 is implied.

This means that the range includes all of 2005-03-01 but none of 2005-04-01.

You may wish to write end="2005-03-31T23:59:59" to avoid confusion.

Example 8.7. A full moon on Friday the 13th


  <rule id="rule7" boolean_op="and">
   <date_expression id="date_expr7" operation="date_spec">
    <date_spec weekdays="5" monthdays="13" moon="4"/>
   </date_expression>
  </rule>