[nikai]

Not even in C. You can have an if condition that is actually a macro that expands with parentheses. For example the macros in ctype.h, so you can actually write

  if islower(c) {
      (..)
  }

[cygx]

That's not portable, though: A comforming implementation may very well implement islower as a function call, and you should treat is as such.

[raverbashing]

Yeah, but macros are not really part of the language, they're more a writing aid than anything really.

So, for the sake of good practices, write if with parenthesis.

[olavk]

That is cheating!