Whitespace and Basic Formatting

Whitespace and Basic Formatting

Whitespace means the "empty" characters: spaces, tabs, and newlines. C shrugs at most of them.

The compiler ignores whitespace

Outside of strings, extra spaces and newlines don't change behaviour:

int x = 5;

int     x   =   5;

Both compile and do the same thing. But the second one is unpleasant!

One place whitespace counts

Inside a string literal, spaces are part of the text:

printf("hello world"); // keeps the space
printf("helloworld");  // different text!

What whitespace is for: readability

Indentation tells you at a glance what belongs inside a block:

int main() {
    if (age > 5) {
        printf("Big kid!");
    }
}

The inner line is indented one more level because it belongs to the if. Even though the compiler doesn't need this, your future self does.

Style notes

• Pick one style (spaces vs tabs, brace on the same line) and stick to it.
• Consistent formatting makes bugs easy to spot, since odd lines "pop out".

TL;DR

• Whitespace = spaces, tabs, and newlines; the compiler ignores it (except inside strings).
• Indentation has no effect, but it's great for readability.
• Indent nested code to show it "belongs to" the block above.
• Stay consistent with your formatting everywhere.