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maprule Expressions
The maprule expression provides information about mapping rules. It is represented in the xfMap document with the <maprule> element, and it has the following general form:
<maprule expr=”...”/>
The expression string (i.e., the expr attribute) specifies the type of mapping rule information.
The following lists the valid values the expression string may take:
activate-count:
<maprule expr=”activate-count”/>
Returns the number of times a mapping rule has been activated.
Example
The example below illustrates several of the counter expression operations.
bin.xml
<?xml version=”1.0”?> <bin> <item>I’m some sort of item inside this bin.</item> <item>What type of item may I be?</item> <item>I wouldn’t know.</item> <item>Why should I?</item> <item>Ask the bin.</item> </bin>
maprule.xmp
<?xml version=”1.0”?> <!DOCTYPE xfMap SYSTEM ”xfMap.dtd”> <xfMap> <feature-map> <mapping match=”item”> <feature-type> <literal expr=”item”/> </feature-type> <attributes> <attribute> <name> <literal expr=”value”/> </name> <value><extract expr=”.”/> </value> </attribute> <attribute> <name> <literal expr=”mapping-rule-activate-count”/> </name> <value><maprule expr=”activate-count”/> </value> </attribute> </attributes> </mapping> </feature-map> </xfMap>
FME features constructed:
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Feature Type: `item' Attribute(string): `mapping-rule-activate-count' has value `1' Attribute(string): `value' has value `I'm some sort of item inside this bin.' Attribute(string): `xml_type' has value `xml_no_geom' Geometry Type: Unknown (0) =================================================================== +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Feature Type: `item' Attribute(string): `mapping-rule-activate-count' has value `2' Attribute(string): `value' has value `What type of item may I be?' Attribute(string): `xml_type' has value `xml_no_geom' Geometry Type: Unknown (0) =================================================================== +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Feature Type: `item' Attribute(string): `mapping-rule-activate-count' has value `3' Attribute(string): `value' has value `I wouldn't know.' Attribute(string): `xml_type' has value `xml_no_geom' Geometry Type: Unknown (0) =================================================================== +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Feature Type: `item' Attribute(string): `mapping-rule-activate-count' has value `4' Attribute(string): `value' has value `Why should I?' Attribute(string): `xml_type' has value `xml_no_geom' Geometry Type: Unknown (0) =================================================================== +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Feature Type: `item' Attribute(string): `mapping-rule-activate-count' has value `5' Attribute(string): `value' has value `Ask the bin.' Attribute(string): `xml_type' has value `xml_no_geom' Geometry Type: Unknown (0) ===================================================================