symbol_table.py

class SymbolTable:
    def __init__(self):
        self.free_address = 16
        self.symbol_table: dict[str, int] = {
            "SP":     0x0000,
            "LCL":    0x0001,
            "ARG":    0x0002,
            "THIS":   0x0003,
            "THAT":   0x0004,
            "R0":     0x0000,
            "R1":     0x0001,
            "R2":     0x0002,
            "R3":     0x0003,
            "R4":     0x0004,
            "R5":     0x0005,
            "R6":     0x0006,
            "R7":     0x0007,
            "R8":     0x0008,
            "R9":     0x0009,
            "R10":    0x000a,
            "R11":    0x000b,
            "R12":    0x000c,
            "R13":    0x000d,
            "R14":    0x000e,
            "R15":    0x000f,
            "SCREEN": 0x4000,
            "KBD":    0x6000
        }

    def add_symbol(self, symbol: str, address: int) -> None:
        print("Adding ", symbol, " to table at ", address)
        self.symbol_table[symbol] = address

    def contains(self, symbol: str) -> bool:
        try:
            return True if self.symbol_table[symbol] != None else False
        except KeyError:
            return False

    def get_address(self, symbol: str) -> int:
        return self.symbol_table[symbol]