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来源：互联网发布：学日语的软件编辑：程序博客网时间：2024/06/05 23:50
int get_token(){    int c, len, i, max_word_len, state, token, flag, pause_line, pause_block;    state = START;    pause_line = 0;    pause_block = 0;    while( state != OVER  )    {        if( state == PAUSE )        {            if( pause_line )            {                pause_line = 0;                pos = input_len;                state = START;            }            if( pause_block )            {                while( (c = get_next_word(&pos)) != FINISH )                {                    if( c == '*' && input_line[pos] == '/' )                    {                        input_line[pos++];                        break;                    }                }                if( c == FINISH )                    return FINISH;                pause_block = 0;                state = START;            }        }        c = get_next_word(&pos);        if( c == FINISH )            return FINISH;        if( c == ' ' || c == '\t' || c == '\n' )            continue;        if( isalpha( c ) || c == '_' )        {            i = 0;            max_word_len = 0;            do            {                save_word[i++] = c;                c = input_line[pos++];                max_word_len++;            }while( isdigit( c ) || c == '_' || isalpha( c ) );            pos--;            if( max_word_len >= 20 )            {                fprintf( stderr, "word's max len is 20"); // do a error deal function                exit( 0 );            }            save_word[i] = '\0';            token = TOK_ID;            state = OVER;        }        else if( isdigit( c ) )        {            i = 0;            if( flag == '-' )                save_word[i++] = '-';            while( isdigit( c ) )            {                save_word[i++] = c;                c = input_line[pos++];            }            pos--;            save_word[i] = '\0';            save_num = atoi( save_word );            token = TOK_NUM;            state = OVER;            flag = 0;        }        else        {            state = OVER;            switch( c )            {                case '+':                    token = TOK_PLUS;                    break;                case '-':                    token = TOK_MINUS;                    break;                case '*':                    token = TOK_MUL;                    break;                case '/':                    if( input_line[pos] == '/' )                    {                        input_line[pos++];                        state = PAUSE;                        pause_line = 1;                    }                    else if( input_line[pos] == '*' )                    {                        input_line[pos++];                        state = PAUSE;                        pause_block = 1;                    }                    else                    {                        token = TOK_DIV;                    }                    break;                case '=':                    if( input_line[pos] == '=' )                    {                        input_line[pos++];                        token = TOK_EQ;                    }                    else                        token = TOK_ASSIGN;                    break;                case '>':                    if( input_line[pos] == '=' )                    {                        input_line[pos++];                        token = TOK_GE;                    }                    else                        token = TOK_GT;                    break;                case '<':                    if( input_line[pos] == '=' )                    {                        input_line[pos++];                        token = TOK_LE;                    }                    else                        token = TOK_LT;                    break;                case '!':                    if( input_line[pos] == '=' )                    {                        input_line[pos++];                        token = TOK_NE;                    }                    else                        token = TOK_NOT;                    break;                case '&':                    if( input_line[pos] == '&' )                    {                        input_line[pos++];                        token = TOK_ANDAND;                    }                    else                        token = TOK_AND;                    break;                case '|':                    if( input_line[pos] == '|' )                    {                        input_line[pos++];                        token = TOK_OROR;                    }                    else                        token = TOK_OR;                    break;                case ',':                    token = TOK_COMMA;                    break;                case ':'://no gonna use 'condition ?  true : false'                    token = TOK_COLON;                    break;                case ';':                    token = TOK_SEMI;                    break;                case 39:    //  '                    token = TOK_SQUTOA;                    break;                case 34:    //  "                    token = TOK_DQUTOA;                    break;                case '(':                    token = TOK_LPAREN;                    break;                case ')':                    token = TOK_RPAREN;                    break;                case '[':                    token = TOK_LSQUARE;                    break;                case ']':                    token = TOK_RSQUARE;                    break;                case '{':                    token = TOK_LBRACKET;                    break;                case '}':                    token = TOK_RBRACKET;                    break;            }        }    }    if( token == TOK_ID )    {        int t;        if( (t = is_resever_word(save_word)) != -1 )            token = t;    }    return token;}
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