#ifndef SCANNER_H
#define SCANNER_H

#define INITIAL_STRING_SIZE 10

// This enum denotes what type of variable a token is.
enum Type {
  EXECUTABLE,    // a command in either $CWD or $PATH
  OPTION,        // any options to pass to an executable or builtin
  COMPOSITION,   // '&&', '||', ';', '\n'
  BUILTIN,       // one of a few pre-defined builtin executables 
  PIPELINE,      // '|'
  REDIRECT,      // '<' or '>'
  BACKGROUND,    // '&'
  FILENAME       // a file (for redirection)
};

typedef struct ListNode *List;

typedef struct ListNode {
    char *t;
    enum Type type;    
    List next;
} ListNode;


#if EXT_PROMPT
char *readInputLine(char const *prompt);
#else
char *readInputLine();
#endif

List getTokenList(char *s);

bool isEmpty(List l);

void printList(List l);

void freeTokenList(List l);

#endif