There's always, and I think this is nearly invariable -there's an element in Milton's similes that stands outside the framework of the basic comparison.
Note in the evaluation, if the pattern is a bound variable, or the element of the pattern is a bound variable, then the result of the pattern match becomes a comparison.
注意，如果模式是绑定的变量，或者模式的元素是绑定的变量，那么模式匹配的结果就会变成比较。
3
The le operator in the last element below is an example of a value comparison operator.