Metamorph Cookbook

Please add recipes under 'Solutions'. If you have a problem in need of a solution, please add it under 'Open Problems'.

Solutions

The following sections present solutions to common problems.

Emitting value of A whenever B occurs

If A happens only once and before Bs:

<combine name="" value="${a}" reset="false">
   <data source="A" name="a"/>
   <data source="B" name=""/>
</combine>

if A happens only once but after Bs, the Bs must be delayed by buffering them:

<combine name="" value="${a}" reset="false">
   <data source="A" name="a"/>
   <data source="B" name="">
      <buffer/>   
   </data>
</combine>

Open Problems

Use recursion to avoid the value of a field to be reset

Four lines of text should be extracted from a pica+ record which all begin with the $f-subfield of the 003@ and are followed by a combination of subfields in each 028@.

003@ ƒ01025201213  
028@ ƒdFarīdƒcal-ƒaʿAbdalāwī  
028@ ƒdFarīdƒaAl-ʿAbdalāwī  
028@ ƒdFarid HamidƒaEl Abdellaouiƒ4nawi  
028@ ƒdFarid HamidƒaAbdellaouiƒlEl  

The rule of metamorph is defined as:

<combine name="${personalname}${surname}${forename}${prefix}${addition}"
        value="##${pid}##,##${personalname}${surname}${forename}${prefix}${addition}##,##V##" 
        flushWith="028@" reset="true">  
    <data source="[email protected]" name="pid"/>
    <data source="[email protected]" name="personalname" />
    <data source="[email protected]" name="surname"/>
    <data source="[email protected]" name="forename"/>
    <data source="[email protected]" name="prefix"/>
    <concat name="addition" delimiter=", " flushWith="028@" reset="true" prefix=" ">
        <data source="[email protected]"/>
        <data source="[email protected]"/>
        <data source="[email protected]"/>
    </concat>
</combine>

The following output is expected:

'##1025201213##,##Abdellaoui, Farid Hamid##,##V##'  
'##1025201213##,##Al-ʿAbdalāwī, Farīd##,##V##'  
'##1025201213##,##El Abdellaoui, Farid Hamid##,##V##'  
'##1025201213##,##ʿAbdalāwī, Farīd al-##,##V##'  

In fact output looks like this:

'##1025201213##,##Abdellaoui, Farid Hamid##,##V##'
'####,##Al-ʿAbdalāwī, Farīd##,##V##'
'####,##El Abdellaoui, Farid Hamid##,##V##'
'####,##ʿAbdalāwī, Farīd al-##,##V##'

The reset=”true” option cleans the 003@ and 028@ before a new 028@ is read. A new 003@ doesn’t exist and it is therefore empty. Neither reset=”false” can be used here, because it will remember the value of the old 028@, like the “al-“ at end of the following lines which in fact only appears in the first 028@ field.

'##1025201213##,##Abdellaoui, Farid Hamid al-##,##V##'
'##1025201213##,##Al-ʿAbdalāwī, Farīd al-##,##V##'
'##1025201213##,##El Abdellaoui, Farid Hamid al-##,##V##'
'##1025201213##,##ʿAbdalāwī, Farīd al-##,##V##'

The solution is use of recursion (prefix @):

<combine name="@pid" value="${pid}" flushWith="028@">
    <data source="[email protected]" name="pid"/>
</combine>

<combine name="${personalname}${surname}${forename}${prefix}${addition}"
        value="##${pid}##,##${personalname}${surname}${forename}${prefix}${addition}##,##V##"
        flushWith="028@" reset="true">  
    <data source="@pid" name="pid"/>  
    <data source="[email protected]" name="personalname" />  
    <data source="[email protected]" name="surname"/>  
    <data source="[email protected]" name="forename"/>  
    <data source="[email protected]" name="prefix"/>  
    <concat name="addition" delimiter=", " flushWith="028A" reset="true" prefix=" ">  
        <data source="[email protected]"/>  
        <data source="[email protected]"/>  
        <data source="[email protected]"/>  
    </concat>  
</combine>  

The first <combine> element use the name “@pid” to declare a redirecting the value return to the input stream and it is done for each new 028@. The second <combine> element uses the redirected, but not reset value of 003@ to combine the new 028@ values which are reset before read.