Coding Style and Best Practices: Descriptive Names, Whitespace, Braces and Comments, Slides of C programming

Download Coding Style and Best Practices: Descriptive Names, Whitespace, Braces and Comments and more Slides C programming in PDF only on Docsity! 1 Why think about style? • By relieving the brain of all unnecessary work, a good notation sets it free to concentrate on more advanced problems, and in effect increases the mental power of the race. -- Alfred North Whitehead, An Introduction to Mathematics. • Moral: program with transparent style – Consistent style – Intuitive style Names • Descriptive names for globals, short names for locals – Comment with declaration is useful for (theElementIndex = 0; theElementIndex < numberOfElements; theElementIndex++) elementArray[theElementIndex] = theElementIndex; for ( i = 0; i < nelems; i++) elem[i] = i; vs. •Local variables – e.g., loop variables, temporary variables have conventional short names: int npending = 0; // current length of input queue a = (b + c*d) * (1+e); vs. total = (parts + labor*hourlyRate) * (1 + taxRate); 2 Names (contd) • Consistency important class UserQueue { int noOfItemsInQ, frontOfTheQueue, queueCapacity; public int noOfUsersInQueue() {…} } vs. class UserQueue { int nitems, front, capacity; public int nusers() {…} } Names (contd) • Long lived and important variables should be introduced with a comment stating its function/meaning in the program • Short mnemonics tend to be good for local variables as context helps for these – e.g., “np” rather than “nodepointer” if mnemonic is part of consistent scheme • Longer names for long-lived/global variables with less context surrounding their usage, also something should indicate that they are not local • Consistency: e.g., related vars named “maxphysaddr” and “lowestaddress” is bad style • Variables should be nouns. Functions should be verbs.