Programming Style Requirements

MIM 3132, C/UNIX for Information Systems

Summer 2001

Programming Style Requirements:
  1. Robustness.
       Check all input for validity. Invalid input should generate an error 
       condition.
  2. Generality
       Program should be as general as possible. Avoid code that refers to 
       specific input. Use constants where appropriate.
  3. Input/Output Behavior
       With interactive programs, prompt the user for correct input. Output
       should be clearly laid out and well labeled. Do not hesitate to use 
       blank lines to improve format.
  4. Modularity
       Break down the program logically into modules.  No global variables!
  5. Global Definitions
       Structure definitions, typedefs, #define-ed constants, and other user-
       defined data types are generally global.  Function prototypes can also
       be global.  Never, under any circumstances, should variables be declared
       global.
  6. Testing
       As input supply both valid and invalid data to ensure your program is
       capable of handing error conditions. Invalid data will be used during 
       the grading process.
  7. Simplicity
       Without loss of generality, keep your program as simple as possible. 
       Concentrate on fulfilling the expectations of the assignment first, 
       and later add any extra features you may choose to include.
  8. Mnemonics
       Select meaningful identifiers for variables, functions, constants, etc.
  9. Documentation
       Comment statements are required. Lack thereof will affect the grade. 
       Good documentation is essential both for the programmer's own reference
       and for grading purposes. Begin the program with your name, the date,
       and a general description of the program, including valid input and 
       expected output. Be sure to state any assumptions here. Explain variable
       definitions, the purpose of functions. Label end brackets. Keep comments
       over to the right as much as possible away from the code. Avoid 
       comments that are so long they "snake" to the next line.
 10. Parameter Passing.
       Do not use variables declared on higher levels unless they have been 
       passed as parameters.
 11. Indentation.
      Follow ANSI guidelines. All blocks of code should be indented a minimum 
      of 3 spaces. Make sure end-brackets line up with the line on which the 
      begin-brackets appears.  End-brackets should not occur on the same line 
      as code. Begin-Brackets should appear on a line of code only if they are
      at the end of the line.  Separate clauses of a compound statement should
      appear on separate lines.


        Example:    if(x==3)                    if(x==3)
                       printf("x equals 3\n");     printf("x equals 3\n");
                    else printf("x not 3\n");   else
						   printf("x not 3\n");

                    while(i<10){              while(i<10)
                       line1;		      { 
		       line2;    	 	line1;   
		       line3;			line2;
		     }                          line3;         
                                              }   

        Unacceptable Styles:
		for(i=0;i<10;i++)printf("%d\n",i);
		
                if(x<y)printf("...");else x=10;