typedef struct charClass {
    unsigned char table[256];
    struct utf8Range {
        unsigned char *begin;
        unsigned char *end;
        struct utf8Range *next;
    } *rangeList;
} CharClass, *CharClassPtr;

typedef struct node {
    unsigned char type;
    union value {
        charClass cc;
        unsigned char character;
    } Value, *ValuePtr;
    struct node *self;
    struct node *parent;
    struct node *left;
    struct node *right;
} Node, *NodePtr;