I am working on an existing project. This project has a number of function calls with the format:

String3 := CONCAT(STR1 := String1, STR2 := String2);

This works properly. My preference would be:

String3 := CONCAT(String1, String2);

This also works. Is there a mention in any coding style documentation that suggests one style or the other?

Could there be a performance difference between the two?

First Style
CPU Step 1: Assign STR1 the value of String1
CPU Step 2: Assign STR2 the value of String2
CPU Step 3: Call CONCAT with STR1 and STR2
VS.
CPU STEP 1: CALL CONCAT with String1 and String2

As far as performance goes, there doesn't seem to be a difference:

As for style, I agree with you, that CONCAT(String1, String2) is more readable, but on more complex functions where the inputs might not be as intuitive, I'll use the names.

Originally created by: rickj

Adding to what TVM said, for large function calls it's common to list parameters on separate lines as shown below. Also note the different notation for input and output parameters.

   Result := SomeFunction(
      Input_01 := in01,         // Input parameters
      Input_02 := in02,
      Input_03 := in03,
         "        "
      Input_99 := in99,
      Output_01 => out01,      // Output parameters
      Output_02 => out02,
   );

rickj hat geschrieben:
Adding to what TVM said, for large function calls it's common to list parameters on separate lines as shown below. Also note the different notation for input and output parameters.

   Result := SomeFunction(
      Input_01 := in01,         // Input parameters
      Input_02 := in02,
      Input_03 := in03,
         "        "
      Input_99 := in99,
      Output_01 => out01,      // Output parameters
      Output_02 => out02,
   );

Thank You!