W,
]
Complex = [
('(', Sentence, ')'),
('[', Sentence, ']'),
(NEG, Sentence),
(Sentence, CON, Sentence),
(Sentence, DIS, Sentence),
(Sentence, IMP, Sentence),
(Sentence, IFF, Sentence),
]
# pprint(E)
# g = Grammar(*E)
# pprint(g)
pprint(E.lex2pats)
p = LALR(E)
# pprint([*p.lexer.tokenize('True & False', True)])
# pprint(p.parse('P & Q | R & !S'))
s = p.dump('meta_dumps.py')
p1 = LALR.load('meta_dumps.py', globals())
# print(s)
pprint(p1.parse('P & Q | R & !S'))
import preamble
from metaparse import LALR
pCalc = LALR()
lex = pCalc.lexer
rule = pCalc.rule
# lex(<terminal-symbol> = <pattern>)
lex(IGNORED=r'\s+')
lex(NUM=r'[0-9]+')
lex(EQ=r'=')
lex(ID=r'[_a-zA-Z]\w*')
# lex(... , p = <precedence>)
lex(POW=r'\*\*', p=3)
lex(POW=r'\^') # No need to give the precedence twice for POW.
lex(MUL=r'\*', p=2)
lex(ADD=r'\+', p=1)
# @rule
# def <lhs> ( <rhs> ):
# <semantics>
@rule
def assign(ID, EQ, expr):
context[ID] = expr
return expr
@rule
import preamble
from metaparse import LALR
calc = LALR()
with calc as (lex, rule):
lex(IGNORED=r'\s+')
@lex(NUM=r'[0-9]+')
def NUM(val):
return int(val)
lex(EQ=r'=')
lex(ID=r'[_a-zA-Z]\w*')
lex(POW=r'\*\*', p=3)
lex(MUL=r'\*', p=2)
lex(ADD=r'\+', p=1)
lex(SUB=r'\-', p=1)
@rule
def assign(ID, EQ, expr):
table[ID] = expr
return expr
@rule
def expr(ID):
return table[ID]
@rule
import preamble
import metaparse as mp
from metaparse import LALR, END_TOKEN
p = LALR()
p.lexer.more(IGNORED=' ', PLUS='\+', TIMES='\*', LEFT='\(', RIGHT='\)')
@p.lexer(NUMBER='\d+')
def _(val):
return int(val)
@p.rule
def expr(expr, PLUS, term):
return expr + term
@p.rule
def expr(term):
return term
@p.rule
def term(term, TIMES, factor):
return term * factor
@p.rule
def term(factor):