Parser

Implementation of LL(0), LR(0), SLR(1), CLR(1) algorithms in C#.

This is done for educational purposes only.

Topics Covered

• First and follow terminals are calculated, even when grammer is left recursive.
• Stack changes are shown in a table.
• For LR algorithms state diagrams are shown in a graph (Microsoft Library MSAGL)
• Syntax Parse tree is shown (Microsoft Library MSAGL)

ToDo

• Add Support for LALR(1) algorithms.
• Add Support to input grammar with | symbol.

How to build parse tree

Use the input from SampleGrammars Folder which is available in Project source Grammars are written in BNF format as show below.

JSON Grammar:

<JSON> ::= <array>
<JSON> ::= <object>

<array> ::= "[" <arrayinside> "]" 

<arrayinside> ::= <value>
<arrayinside> ::= <value> "," <arrayinside>
<arrayinside> ::= ""

<object> ::= "{" <objectinside> "}"

<objectinside> ::= <pair>
<objectinside> ::= <pair> "," <objectinside>
<objectinside> :: ""

<pair> ::= <string> ":" <value>

<value> ::= <string>
<value> ::= <number>
<value> ::= <object>
<value> ::= <array>
<value> ::= "True"
<value> ::= "False"
<value> ::= "null"

<string> ::= "a"
<string> ::= "b"
<string> ::= "c"
<string> ::= "d"

<number> ::= "1"
<number> ::= "2"
<number> ::= "3"
<number> ::= "4"

JSON test:

    { a : 1 , b : [ 1 , 3 , a , { a : 2 , c : 4 , } , ] , c : False , b : True , }