ABSTRACT

A parser is one of the components in an interpreter or compiler, which checks for correct syntax and builds a data structure (often some kind of parse tree, abstract syntax tree or other hierarchical structure) implicit in the input tokens. Parsers may be programmed by hand or may be (semi-)automatically generated by a parser generating tool. Various techniques are available for parsing formal languages. The objective of this paper is to compare these techniques. The paper is organized in two sections. The first section does discuss about the parsing problem and process. In the second section we study and compare three parsing techniques theoretically .Finally the paper concludes with the suggestion of a new parsing technique.