Editing Programming style (section)

=== Whitespace ===
A [[free-format language]] ignores [[whitespace character]]s: spaces, tabs and new lines so the programmer is free to style the code in different ways without affecting the meaning of the code. Generally, the programmer uses style that is considered to enhance [[readability]].

The two code snippets below are the same logically, but differ in whitespace.

<syntaxhighlight lang="c">
int i;
for(i=0;i<10;++i){
    printf("%d",i*i+i);
}
</syntaxhighlight>
versus 
<syntaxhighlight lang="c">
int i;
for (i = 0; i < 10; ++i) {
    printf("%d", i * i + i);
}
</syntaxhighlight>

The use of [[Tab key|tabs]] for whitespace is debatable. Alignment issues arise due to differing tab stops in different environments and mixed use of tabs and spaces.

As an example, one programmer prefers [[tab stop]]s of four and has their toolset configured this way, and uses these to format their code.

<syntaxhighlight lang="c">
int     ix;     // Index to scan array
long    sum;    // Accumulator for sum
</syntaxhighlight>

Another programmer prefers tab stops of eight, and their toolset is configured this way. When someone else examines the original person's code, they may well find it difficult to read.

<syntaxhighlight lang="c">
int             ix;             // Index to scan array
long    sum;    // Accumulator for sum
</syntaxhighlight>

One widely used solution to this issue may involve forbidding the use of tabs for alignment or rules on how tab stops must be set. Note that tabs work fine provided they are used consistently, restricted to logical indentation, and not used for alignment:

<syntaxhighlight lang="cpp">
class MyClass {
	int foobar(
		int qux, // first parameter
		int quux); // second parameter
	int foobar2(
		int qux, // first parameter
		int quux, // second parameter
		int quuux); // third parameter
};
</syntaxhighlight>