// Issue #635: optimized for loop with := must not produce dangling values
// := is reference-assign, so ret aliases i and sees the loop exit value

// Basic: capture loop variable via :=
var ret = 0
for (var i = 0; i < 100; ++i) {
  ret := i
}
assert_equal(100, ret)

// Return from function containing optimized for loop
def loop_result() {
  var ret = 0
  for (var i = 0; i < 200; ++i) {
    ret := i
  }
  return ret
}
assert_equal(200, loop_result())

// Multiple calls return consistent results
assert_equal(loop_result(), loop_result())

// Nested optimized for loops
var outer_val = 0
var inner_val = 0
for (var i = 0; i < 10; ++i) {
  for (var j = 0; j < 10; ++j) {
    inner_val := j
  }
  outer_val := i
}
assert_equal(10, outer_val)
assert_equal(10, inner_val)

// Value-assign (=) captures last body-iteration value, not exit value
var ret2 = 0
for (var i = 0; i < 100; ++i) {
  ret2 = i
}
assert_equal(99, ret2)