"[SOLVED] empty-string macro in Execute Process operator"

tennenrishin

Hi all

Is there a way to denote an empty string in the "macro value" field of the "macros" parameter of the "Execute Process" operator.

If I leave it blank, the entire macro seems to be discarded automatically.

Thanks in advance
Isak

MariusHelf

Hi Isaac,

no, that's currently not possible. If you really need it you could use the Generate Macro with the replace() function. I admit it's not the most elegant thing, but it works. Please see the attached process.

Best, Marius

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<process version="5.2.006">
  <context>
    <input/>
    <output/>
    <macros/>
  </context>
  <operator activated="true" class="process" compatibility="5.2.006" expanded="true" name="Process">
    <process expanded="true" height="280" width="614">
      <operator activated="true" class="set_macro" compatibility="5.2.006" expanded="true" height="76" name="Set Macro" width="90" x="179" y="30">
        <parameter key="macro" value="x"/>
        <parameter key="value" value="a"/>
      </operator>
      <operator activated="true" class="generate_macro" compatibility="5.2.006" expanded="true" height="76" name="Generate Macro" width="90" x="313" y="30">
        <list key="function_descriptions">
          <parameter key="x" value="replace(&quot;%{x}&quot;, &quot;a&quot;, &quot;&quot;)"/>
        </list>
      </operator>
      <operator activated="true" class="print_to_console" compatibility="5.2.006" expanded="true" height="76" name="Print to Console" width="90" x="447" y="30">
        <parameter key="log_value" value="x: &quot;%{x}&quot;"/>
      </operator>
      <connect from_op="Set Macro" from_port="through 1" to_op="Generate Macro" to_port="through 1"/>
      <connect from_op="Generate Macro" from_port="through 1" to_op="Print to Console" to_port="through 1"/>
      <connect from_op="Print to Console" from_port="through 1" to_port="result 1"/>
      <portSpacing port="source_input 1" spacing="0"/>
      <portSpacing port="sink_result 1" spacing="0"/>
      <portSpacing port="sink_result 2" spacing="0"/>
    </process>
  </operator>
</process>

Oh, I just saw that you need it for Execute Process. That's not possible, however you could define a string representing "empty" and replace it with empty in the executed process with the above operators.