Script Variables¶

script_variables - Define variables that can be shared between scripts¶

The script_variables command allows users to declare a set of variables that are accessible to scripts within a given context. For example, if the script_variables command is used inside the platform command, then all scripts defined within that platform have access to the variables that were are defined. In addition, child contexts such as script processors, task managers, state machines can access these variables by using the ‘extern’ keyword. The syntax to define variables is exactly the same as used inside of the script command because it uses the same compiler.

Command Template¶

script_variables
   variable declaration or variable assignment
end_script_variables

Examples¶

Examples of how variables can be defined in the script_variables command:

platform_type MY_PLATFORM_TYPE WSF_PLATFORM
   script_variables

      int mMyInt = 9;

      int mMyDouble = 1.23456;

      Array<string> mMyArray = Array<string>();
      mMyArray[0] = 'hello';
      mMyArray[1] = 'world';

      mMyDouble = -mMyDouble;

      mMyInt = mMyDouble + 100;

   end_script_variables

   on_initialize
      writeln("mMyInt=", mMyInt);    // The on_initialize script can access the mMyInt variable
                                     // that was defined in current context (i.e. the platform).
   end_on_initialize

   processor script-processor-1 WSF_SCRIPT_PROCESSOR
      on_initialize
         extern int mMyInt;          // To access the mMyInt variable defined by the parent platform the
                                     // script processor must first extern it.
         writeln("mMyInt=", mMyInt);
      end_on_initialize
   end_processor

   processor script-processor-2 WSF_SCRIPT_PROCESSOR
      script_variables
         int mMyInt = 12;            // If a child context (i.e. the script processor) defines a script variable
                                     // with the same name as a variable in the parent's context (i.e. the platform)
                                     // it creates its own copy that is independent of the parents.
      end_script_variables

      on_initialize
         writeln("mMyInt=", mMyInt); // This will print 12.
      end_on_initialize
   end_processor
end_platform

As shown, one can declare and assign variables using the same syntax as in a script. Function and script calls, as well as branching (e.g., if, else) and looping logic (e.g., for, while) are prohibited.

Script Variables¶