Hmm, I seem to get the opposite. The same code with less brackets and parenthesis appears to be faster..

Code:
alias test1 var %y = 0 | if 1 == 1 && %y == 0 return 1

alias test2 { var %y = 0 | if (1 == 1) && (%y == 0 ) { return 1 } }

alias runtest {

  var %i = 0
  var %t = $ticks

  while (%i < 100000) {
    test1
    inc %i
  }

  echo -a test1 --- $calc($ticks - %t) ms

  var %i = 0
  var %t = $ticks

  while (%i < 100000) {
    test2
    inc %i
  }

  echo -a test2 --- $calc($ticks -%t) ms
}



result
Quote:
test1 --- 3198 ms
test2 --- 3276 ms