# XQuery-specific expressions

# If-then-else
if (true()) then "yes" else "no"
if (count(//error) > 0) then "errors" else "ok"
if ($x > 0) then $x else -$x

# Quantified expressions
some $x in (1, 2, 3) satisfies $x > 2
every $x in (1, 2, 3) satisfies $x > 0
some $x in //price, $y in //discount satisfies $x > $y

# Value comparison operators
$a eq $b
$x ne 0
$price lt 100
$age le 65
$score gt 90
$count ge 1

# Node comparison
$a is $b

# Range expression
1 to 10

# Sequence expression
(1, 2, 3)
("a", "b", "c")
(1, "two", 3.0)

# Empty sequence
()

# Integer division
10 idiv 3

# Union/intersect/except
$a union $b
$a intersect $b
$a except $b
//book | //article

# Parenthesized expressions
(for $x in (1, 2) return $x * 2)
(if (true()) then 1 else 2) + 3