What's the purpose of using braces (i.e. {}) for a single-line if or loop?

Question

I'm reading some lecture notes of my C++ lecturer and he wrote the following: > 1. Use Indentation // OK> 2. Never rely on operator precedence - Always use parentheses // OK > 3. Always use a { } block - even for a single line // **not OK**, why ???> 4. Const object on left side of comparison // OK > 5. Use unsigned for variables that are >= 0 // nice trick > 6. Set Pointer to NULL after deletion - Double delete protection // not badThe 3rd technique is not clear to me: what would I gain by placing one line in a `{ ... }`? For example, take this weird code: int j = 0; for (int i = 0 ; i < 100 ; ++i) {  if (i % 2 == 0)  {   j++;  } }and replace it with:  int j = 0; for (int i = 0 ; i < 100 ; ++i)  if (i % 2 == 0)   j++;What's the benefit of using the 1st version?

Answer 1

Main reason for being a pseudo best-practice: consistency in appearance and easier to modify ... as very simple code blocks can get more complex over time - very easy to go

FROM

condition

{

line 1;

}

TO

condition

{

line 1;

line 2;

line 3;

}

without accidentally introducing a logical bug

condition // no braces

line 1;

line 2; // inadvertently omitted

line 3; // inadvertently omitted

I understand why the language allows it, but I almost wish the C/C++ compilers disallowed single-line code blocks with no { }