📚 FP-2025: Library Management System

This project implements a domain-specific language (DSL) for managing a library. Users can add/remove books, borrow/return them, search by keyword, and execute batch commands. The DSL is defined by a BNF grammar and parsed into algebraic data types.

Application Domain: Library Management System – Track books and users efficiently!

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🏗️ Main Components

• Book: Identified by a title (String, e.g., "The Great Gatsby").
• User: A person who can borrow and return books (String, e.g., "Alice").
• Command: DSL operations that manipulate the library state.

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🔧 Command Examples

All strings must be enclosed in double quotes ("..."). Whitespace is optional around keywords and separators.

• Add a book:
  AddBook "The Great Gatsby"

• Remove a book:
  RemoveBook "1984"

• Borrow a book:
  BorrowBook "Alice" "The Great Gatsby"

• Return a book:
  ReturnBook "Alice" "The Great Gatsby"

• Search for a book:
  SearchBook "Gatsby"

• Batch multiple commands:
  Batch AddBook "1984" ; BorrowBook "Bob" "1984" ; Dump Examples

• Dump examples:
  Dump Examples

Note: Supports spaces in titles (e.g., "Harry Potter and the Philosopher's Stone") and symbols like . , ! ? - _.

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📝 BNF Grammar

<program> ::= <command>

<command> ::= <add_book> | <remove_book> | <borrow_book> | <return_book> | <search_book> | <dump> | <batch>

<add_book> ::= "AddBook" <ws> <string>
<remove_book> ::= "RemoveBook" <ws> <string>
<borrow_book> ::= "BorrowBook" <ws> <string> <ws> <string>
<return_book> ::= "ReturnBook" <ws> <string> <ws> <string>
<search_book> ::= "SearchBook" <ws> <string>
<dump> ::= "Dump" <ws> "Examples"

<batch> ::= "Batch" <ws> <command_list>

<command_list> ::= <command> ( ";" <ws> <command> )*

<string> ::= <chars>

<chars> ::= <char>

<char> ::= <letter> | <digit> | " " | "." | "," | "!" | "?" | "-" | "_"

<letter> ::= "a" | "b" | "c" | "d" | "e" | "f" | "g" | "h" | "i" | "j" | "k" | "l" | "m" | "n" | "o" | "p" | "q" | "r" | "s" | "t" | "u" | "v" | "w" | "x" | "y" | "z" 
           | "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | "J" | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | "S" | "T" | "U" | "V" | "W" | "X" | "Y" | "Z"

<digit> ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"

<ws> ::= " "*