Rudder

Problem has nothing to do with the generic method in itself.
In the ncf technique generated by the technique we have:

    "method_call" usebundle => variable_string_from_math_expression("my_math", "variable1", "${my_math.variable1}*4", "%d"),
      ifvarclass => concat("any");

But Since "${my_math.variable1}*4" will change value after each execution of the line, the "variable_string_from_math_expression" will be call
in each pass of cfengine.

Still, this break the reporting for unknown reasons

At execution, the method_call_context_ is not reevalued, and so, only the method_call_context_ for the command execution was executed.

=> We should force the technique editor techniques to execute only the pass1.

# @name testing math stuff
# @description 
# @version 1.0

bundle agent testing_math_stuff
{
  methods:
    "method_call_context_0" usebundle => _method_reporting_context("Variable string", "variable1");
    "method_call" usebundle => variable_string("my_math", "variable1", "256"),
      ifvarclass => concat("any");
    "method_call_context_1" usebundle => _method_reporting_context("Variable string from math expression", "variable1");
    "method_call" usebundle => variable_string_from_math_expression("my_math", "variable1", "${my_math.variable1}*4", "%d"),
      ifvarclass => concat("any");
    "method_call_context_2" usebundle => _method_reporting_context("Condition from variable match", "ok_var");
    "method_call" usebundle => condition_from_variable_match("ok_var", "math.math", "1024"),
      ifvarclass => concat("any");
    "method_call_context_3" usebundle => _method_reporting_context("Command execution", "echo '${my_math.variable1} equals 1024' > /tmp/result"),
    "method_call" usebundle => command_execution("echo '${my_math.variable1} equals 1024' > /tmp/result"),
      ifvarclass => concat("any.(ok_var_true)");
}