Coding: Line Breaks

If a loop or conditional has a short enough statement (i.e., loop body, or what to do if the condition is true) that it can all fit on one line without squishing out whitespace to the point of being difficult to read, you may keep it on one line. Otherwise, it must go on a separate line. For example:

  /*
   * acceptable this way, or without block delimiters,
   * but NOT all on one line
   */
  if (very_long_logical_expression)
  {
    very_long_variable = other_long_variable + yet_another;
  }

  /* acceptable any of the three ways */
  if (short_expr) short_var = other_short_var + yet_another;

If either the condition/loop predicate or the statement, or both, must go on multiple lines itself, the statement should be surrounded by block delimiters. For example, the following two are acceptable as shown, but NOT without block delimiters:

  if (logical_expression)
  {
    printf ("The %s %s %s %ss %s the %s %s.\n",
            description1a,
            description1b,
            animal1,
            action,
            adverb,
            description2,
            animal2);
  }

  if (widgetPtr->height > globalParms.maxWidgetHeight ||
      widgetPtr->width > globalParms.maxWidgetWidth)
  {
    printf ("Widget %d is too big\n", widgetNum);
  }

In C, if a "for" loop's initializer, condition, and reinitializer cannot all fit on one line, they should be stacked so that the starts of the condition and reinitializer are directly below the start of the initializer. For example:

  for (longVariableName = 0;
       longVariableName < upperLimit;
       longVariableName++)

Likewise, any function call, while-loop condition, etc. that cannot fit on one line, should be further indented. There are three alternative methods:

• Indent them more than one control level's worth of spaces, but not as far as the first argument to a function call. This is useful when that is very far over, such as when assigning the result of a function with a long name, to an lvalue with a long name. For example:

    veryLongVariableName = VeryLongFunctionName (variable1,
            variable2, variable3, variable4, variable5, variable6);
  

• Stack them below the first argument, one per line. This is useful when the arguments are easy to mix up, need comments for any other reason, or are long. For example:

    variableName = FunctionName (variable1,
                                 variable2,
                                 variable3,
                                 variable4,
                                 variable5,
                                 variable6);

• Stack them below the first argument, multiple per line. For example:

    variableName = FunctionName (variable1, variable2, variable3,
                                 variable4, variable5, variable6);