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# parser.py
import ply.yacc as yacc
from lexer import tokens
# AST node types
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 : program 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(p):
"""instruction : MOV REGISTER COMMA NUMBER
| ADD REGISTER COMMA REGISTER
| JMP IDENT"""
op = p[1]
args = p[2:]
p[0] = Instr(op, args)
def p_empty(p):
"empty :"
p[0] = None
def p_error(p):
raise SyntaxError("Syntax error")
parser = yacc.yacc()
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