Big-Data-HPC-Platform/docs/ECLStandardLibraryReference/SLR-Mods/GetParseTree.xml

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<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<sect1 id="GetParseTree">
  <title>GetParseTree</title>

  <para><emphasis role="bold">STD.System.Debug.GetParseTree<indexterm>
      <primary>STD.System.Debug.GetParseTree</primary>
    </indexterm> <indexterm>
      <primary>System.Debug.GetParseTree</primary>
    </indexterm> <indexterm>
      <primary>Debug.GetParseTree</primary>
    </indexterm> <indexterm>
      <primary>GetParseTree</primary>
    </indexterm>(</emphasis> <emphasis> </emphasis> <emphasis
  role="bold">)</emphasis></para>

  <informaltable colsep="1" frame="all" rowsep="1">
    <tgroup cols="2">
      <colspec colwidth="80.50pt" />

      <colspec />

      <tbody>
        <row>
          <entry>Return:<emphasis> </emphasis></entry>

          <entry>GetParseTree returns a STRING value.</entry>
        </row>
      </tbody>
    </tgroup>
  </informaltable>

  <para>The <emphasis role="bold">GetParseTree </emphasis>function returns a
  textual representation of the match that occurred, using square brackets
  (such as: a[b[c]d] ) to indicate nesting. This function is only used within
  the RECORD or TRANSFORM structure that defines the result of a PARSE
  operation. This function is useful for debugging PARSE operations.</para>

  <para>Example:</para>

  <programlisting format="linespecific">IMPORT STD;

r := {string150 line};
d := dataset([
{'Ge 34:2 And when Shechem the son of Hamor the Hivite, '+
 'prince of the country, saw her, he took her, and lay with her, '+
 'and defiled her.'},
{'Ge 36:10 These are the names of Esaus sons; Eliphaz the son of '+
 'Adah the wife of Esau, Reuel the son of Bashemath the wife of '+
 'Esau.'}
],r);
PATTERN ws := [' ','\t',',']*;
PATTERN patStart := FIRST | ws;
PATTERN patEnd := LAST | ws;
PATTERN article := ['A','The','Thou','a','the','thou'];
TOKEN patWord := PATTERN('[a-zA-Z]+');
TOKEN Name := PATTERN('[A-Z][a-zA-Z]+');
RULE Namet := name OPT(ws 'the' ws name);
PATTERN produced_by := OPT(article ws) ['son of','daughter of'];
PATTERN produces_with := OPT(article ws) ['wife of'];
RULE progeny := namet ws ( produced_by | produces_with ) ws namet;
results := RECORD
  STRING LeftName   := MATCHTEXT(Namet[1]);
  STRING RightName  := MATCHTEXT(Namet[2]);
  STRING LinkPhrase := IF(MATCHTEXT(produced_by[1])&lt;&gt;'',
                         MATCHTEXT(produced_by[1]),
                         MATCHTEXT(produces_with[1]));
  STRING Tree       := 'Tree: ' + STD.System.Debug.getParseTree();
END;
outfile1 := PARSE(d,line,progeny,results,SCAN ALL);
/* the Tree field output looks like this:
Tree: [namet[name"Shechem"] ws" " produced_by"the son of" ws" " namet[name"Hamor"]]
*/</programlisting>
</sect1>