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# parser.py
import ply.yacc as yacc
from lexer import tokens
class Label:
def __init__(self, name):
self.name = name
class Instr:
def __init__(self, op, args):
self.op = op
self.args = args
def p_program(p):
"""program : lines"""
p[0] = p[1]
def p_lines(p):
"""lines : lines line
| line"""
if len(p) == 2:
p[0] = [p[1]]
else:
p[0] = p[1] + [p[2]]
def p_line(p):
"""line : label
| instruction
| empty"""
p[0] = p[1]
def p_label(p):
"""label : IDENT COLON"""
p[0] = Label(p[1])
def p_instruction_mov(p):
"""instruction : MOV REGISTER COMMA NUMBER"""
p[0] = Instr("mov", [p[2], p[4]])
def p_instruction_add(p):
"""instruction : ADD REGISTER COMMA REGISTER"""
p[0] = Instr("add", [p[2], p[4]])
def p_instruction_jmp(p):
"""instruction : JMP IDENT"""
p[0] = Instr("jmp", [p[2]])
def p_empty(p):
"empty :"
p[0] = None
def p_error(p):
raise SyntaxError("Syntax error")
parser = yacc.yacc()
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