Postgenerator

Sometimes you want to be able to merge two tokens in output, for example for contractions, e.g. de + el = del.

You can do this using the postgenerator.

First make sure you add the postgenerator wakeup symbol to your monolingual dictionary, e.g. apertium-aaa.aaa.dix

apertium-aaa.aaa.dix:

   <pardef n="/de__pr">
     <e r="LR"><p><l>de</l><r>de<s n="pr"/></r></p></e>
     <e r="RL"><p><l><a/>de</l><r>de<s n="pr"/></r></p></e>
   </pardef>

...

   <e lm="de"><i></i><par n="/de__pr"/></e>

...

You should get entries like:

de:>:de<pr>
~de:<:de<pr>

from lt-expand apertium-aaa.aaa.dix. apertium-aaa.post-aaa.dix:

<?xml version="1.0" encoding="UTF-8"?>
<dictionary>
  <alphabet/>
  <sdefs>
    <sdef n="test"/>
  </sdefs>
  <section id="main" type="standard">

     <e> <p><l><a/>de<b/>el</l><r>del</r></p></e>
  </section>
</dictionary>

You can compile it like:

$ lt-comp lr apertium-aaa.post-aaa.dix aaa.autopgen.bin
main@standard 7 6

And use it like:

$ echo "~de el" | lt-proc -p aaa.autopgen.bin 
del

In your modes file:

...
      <program name="lt-proc $1">
        <file name="aaa-bbb.autogen.bin"/>
      </program>
      <program name="lt-proc -p">
        <file name="aaa-bbb.autopgen.bin"/>
      </program>
...

Postgeneration Using apertium-separable

If you have at least version 0.7.0 of apertium-separable, you can accomplish the same as above using lsx-proc.

This allows you to write postgeneration rules conditioned on lemmas and tags rather than needing multiple copies of each relevant dictionary entry.

For the de + el → del rule above, we can write the following:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <dictionary>
 3   <alphabet/>
 4   <sdefs>
 5     <sdef n="test"/>
 6   </sdefs>
 7   <section id="main" type="standard">
 8     <e>
 9       <i>de<s n="pr"/>/d</i>
10       <p><l>e</l><r></r></p>
11       <i><d space="no"/>el<t/>/el</i>
12     </e>
13   </section>
14 </dictionary>