Compiler : For Definition [ Click Here ]
Different phases of compilers :
- Analysis Phase
- Synthesis Phase
1.Analysis Phase :
- Lexical analysis
- Syntax analysis
- Semantic analysis
Lexical Analysis Phase :
- Lexical Analyzer is First Phase Of Compiler.
- Input to Lexical Analyzer is “Source Code“
- Lexical Analysis Identifies Different Lexical Units in a Source Code.
- Different Lexical Classes or Tokens or Lexemes
- Identifiers
- Constants
- Keywords
- Operators
- Example : sum = num1 + num2 ;
So Lexical Analyzer Will Produce Symbol Table -
| Token | Type |
| sum | Identifier |
| = | Operator |
| num1 | Identifier |
| + | Operator |
| num2 | Identifier |
| ; | Seperator |
- Lexical Analyzer is also called “Linear Phase” or “Linear Analysis” or “Scanning“
- Individual Token is also Called Lexeme
- Lexical Analyzer’s Output is given to Syntax Analysis.

