tame/core/cond.xml

<?xml-stylesheet type="text/xsl" href="summary.xsl"?>
<lv:package
  xmlns:lv="http://www.lovullo.com/rater"
  xmlns:c="http://www.lovullo.com/calc"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.lovullo.com/rater ../rater.xsd"

  core="true"

  name="core/cond"
  desc="Generic conditionals">

  <lv:import package="base" />


  <!-- TODO: use reduce once we have support for function passing -->
  <lv:function name="or" desc="Return value A if non-zero, otherwise B">
    <lv:param name="or_a" type="float" desc="Value to return if non-zero" />
    <lv:param name="or_b" type="float" desc="Value to return if A is zero" />

    <c:cases>
      <!-- return B if A is zero -->
      <c:case>
        <c:when name="or_a">
          <c:eq>
            <c:const value="0" type="integer" desc="Return B if A is 0" />
          </c:eq>
        </c:when>

        <c:value-of name="or_b" />
      </c:case>

      <!-- return A if non-zero -->
      <c:otherwise>
        <c:value-of name="or_a" />
      </c:otherwise>
    </c:cases>
  </lv:function>


  <lv:template name="_cond_" desc="Conditional shorthand">
    <lv:param name="@name@" desc="Value to check" />
    <lv:param name="@index@" desc="Index of boolean value" />
    <lv:param name="@value@" desc="Constant value" />
    <lv:param name="@type@" desc="Value type" />

    <lv:param name="@cond@" desc="Value to compare against (default boolean true)">
      <lv:text>TRUE</lv:text>
    </lv:param>

    <lv:param name="@desc@" desc="Value description">
      <lv:text>Value when </lv:text>
      <lv:param-value name="@name@" />
    </lv:param>

    <c:const value="@value@" type="@type@" desc="@desc@">
      <!-- TODO: non-index option -->
      <c:when name="@name@" index="@index@">
        <c:eq>
          <c:value-of name="@cond@" />
        </c:eq>
      </c:when>
    </c:const>
  </lv:template>


  <lv:template name="_yield-unless_" desc="Yield a value unless another value is set">
    <lv:param name="@name@" desc="Overriding value" />
    <lv:param name="@index@" desc="Index" />
    <lv:param name="@values@" desc="Value to use otherwise" />

    <c:cases>
      <c:case>
        <lv:if name="@index@">
          <c:when name="@name@" index="@index@">
            <c:gt>
              <c:const value="0" type="integer" desc="Use override if greater than 0" />
            </c:gt>
          </c:when>
        </lv:if>
        <lv:unless name="@index@">
          <c:when name="@name@">
            <c:gt>
              <c:const value="0" type="integer" desc="Use override if greater than 0" />
            </c:gt>
          </c:when>
        </lv:unless>

        <lv:if name="@index@">
          <c:value-of name="@name@" index="@index@" />
        </lv:if>
        <lv:unless name="@index@">
          <c:value-of name="@name@" />
        </lv:unless>
      </c:case>

      <c:otherwise>
        <lv:param-copy name="@values@" />
      </c:otherwise>
    </c:cases>
  </lv:template>


  <lv:template name="_default_" desc="Set a default value if a value is not set">
    <lv:param name="@name@" desc="Param name" />
    <lv:param name="@index@" desc="Index" />
    <lv:param name="@default@" desc="Default value to use if empty" />

    <c:cases>
      <c:case>
        <c:when name="@name@" index="@index@">
          <c:eq>
            <c:const value="0" type="integer" desc="No value" />
          </c:eq>
        </c:when>

        <c:const value="@default@" type="integer" desc="Default value" />
      </c:case>

      <c:otherwise>
        <c:value-of name="@name@" index="@index@" />
      </c:otherwise>
    </c:cases>
  </lv:template>



  <lv:template name="_cond-value-each_" desc="Conditional value">
    <lv:param name="@class@"     desc="Class match" />
    <lv:param name="@generates@" desc="Variable to generate into" />
    <lv:param name="@value@"     desc="Value to yield (use either this or const)" />
    <lv:param name="@const@"     desc="Constant to yield (use either this or value)" />
    <lv:param name="@count@"     desc="Optional number of times to apply const/value (as a variable)" />

    <lv:param name="@desc@" desc="Optional constant description">
      <lv:text>Constant value</lv:text>
    </lv:param>

    <!-- simply returns a constant value for the class match -->
    <lv:rate-each class="@class@" accumulate="none" generates="@generates@" index="k">
      <c:product>
        <lv:if name="@value@">
          <c:value-of name="@value@" />
        </lv:if>
        <lv:unless name="@value@">
          <c:const value="@const@" type="float" desc="@desc@" />
        </lv:unless>

        <!-- if this is not provided, then the c:product will be optimized away -->
        <lv:if name="@count@">
          <c:value-of name="@count@" index="k" />
        </lv:if>
      </c:product>
    </lv:rate-each>
  </lv:template>
</lv:package>