摘要:
本文叙述了在通常的文法中引入两个基元间连接属性的重要性,从而看出在属性文法
中,句法和词意两部分间可以有折衷的关系,即增加后者的复杂性将会使前者得到简化,反之
亦然,这样使便于应用的有限状态属性文法成为基本的形式.这里作者吸取了PDL,Plex
Grammar,Tree Grammar中连接关系的优点,引入连接属性,提出一类关联属性文法.这类
文法可以有效地描述和识别曲线段构成的图形,如汉字、电子线路图等.
Abstract:
The introducing of the concatenation attributes to a conventional grammar is briefly
recommended first. It is emphasized that there is a trade-off between syntactic and
semantic complexities in grammar definition. Various concatenation relations of PDL,
plex grammar, tree grammar are referred. Then a new relational attributed grammar is
proposed in this paper. The pictorial patterns such as circuit diagram, Chinese character
could be described effectively by the relational attributed grammars.