Beautiful C++: 30 Core Guidelines for Writing Clean, Safe, and Fast Code

Chapter 5.4

ES.22: Don’t declare a variable until you have a value to initialize it with

The importance of expressions and statements

This is the fourth guideline from the ES section of the Core Guidelines, Expressions and Statements, to which we have devoted a chapter. One reason for that is the size of this section (over sixty items), but more importantly it gets to the heart of C++. The section opens with the following:

“Expressions and statements are the lowest and most direct way of expressing actions and computation.”

This guideline binds together with ES.5: “Keep scopes small” and ES.10: “Declare one name (only) per declaration.” As you saw in ES.5, keeping scopes small is a great improvement to readability, since scope creates context. ...