# 3.1: binary operators
# `+` add
# `-` sub
# `*` mul
# `/` div
# `>` greater
# `<` less
# `<=` greater equal
# `>=` less equal
# `==` equal
# `!=` not equal
# `&&` and
# `||` or


# 3.2: unary operators
# `!` not
# `typeof` typeof