The DLR USES expression trees to represent languagesemantics.
DLR使用表达式树来表示语言语义。
2
Note the strength of the matching here: we are not merely dealing with wildcards, but languagesemantics.
请注意这里匹配的优势：我们不仅仅处理通配符，而且处理语言语义。
3
From the language design perspective, an external DSL provides the greatest flexibility, since internal DSLs must respect the parsing and languagesemantics of the host language.