parser.py

from dataclasses import dataclass

@dataclass
class Select:
    columns: list
    table: str
    where: tuple = None
    order_by: str = None
    limit: int = None

class Parser:
    def __init__(self, tokens):
        self.tokens = tokens
        self.pos = 0

    def expect(self, type, value=None):
        token = self.tokens[self.pos]
        if token.type!= type or (value and token.value!= value):
            raise SyntaxError(f"Beklenen {type} ama {token.value} bulundu")
        self.pos += 1
        return token

    def parse_select(self):
        self.expect('KEYWORD', 'SELECT')
        columns = ['*'] if self.tokens[self.pos].type == 'STAR' else []
        if columns == []:
            while self.tokens[self.pos].type == 'IDENT':
                columns.append(self.tokens[self.pos].value)
                self.pos += 1
                if self.tokens[self.pos].type == 'COMMA': self.pos += 1
        else: self.pos += 1

        self.expect('KEYWORD', 'FROM')
        table = self.expect('IDENT').value
        return Select(columns, table)