syntax tree的用法和样例：
例句
- This paper introduced a kind of variable type collecting method, which is based on layered thoughtway and abstract syntax tree.
摘要提出了一种基于分层思想的，并且无需构造具体语法树的变量类型提取方法。 - In order to cooperate with the popular bytecode, we propose a bridge mechanism to interconnect the interpretations of both bytecode and the syntax tree.
为配合目前被广泛使用的位元组码，我们还提出语法树与位元组码之间的衔接机制，让这两种不同的直译机制可以互相呼叫。
