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Compiler Design

Foundations of Compilation4

Lexical Analysis6

What is a token? Chopping code into words
Regular expressions and formal languages, from scratch
Finite automata, from NFA to DFA
DFA minimization, and how a lexer reads input fast
Building a real lexer in C++, character by character
Lexer edge cases and error recovery

Parsing & Grammars7

Syntax-Directed Translation & Semantics5

Runtime Environments4

Intermediate Code Generation4

Local Optimization & Data Flow Analysis5

Design Your First Compiler6

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Compiler Design

Foundations of Compilation4

Lexical Analysis6

What is a token? Chopping code into words
Regular expressions and formal languages, from scratch
Finite automata, from NFA to DFA
DFA minimization, and how a lexer reads input fast
Building a real lexer in C++, character by character
Lexer edge cases and error recovery

Parsing & Grammars7

Syntax-Directed Translation & Semantics5

Runtime Environments4

Intermediate Code Generation4

Local Optimization & Data Flow Analysis5

Design Your First Compiler6

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Finite automata, from NFA to DFA

The state-machine "board game" that makes regular expression matching actually fast, and the mechanical algorithm that turns a flexible NFA into a fast, deterministic DFA.

12 min readUpdated 2026-09-03compiler-designlexical-analysisfinite-automatanfadfamath