def _logical(op):
return lexeme(pc.char('(').skip(
lexeme(string(op.call_name)).skip(
many_list(expr).bind(lambda exprs:
pc.char(')').skip(
inject(op(*exprs)))))))
fixnum = concat(optional(oneOf('+-')).bind(lambda sign: inject(sign or '')),
choice(zero, concat(positive_digit, many(digit)))).bind(lambda i:
inject(Fixnum(int(i))))\
.with_name('fixnum')
bool = pc.char('#').skip(
oneOf('tf').bind(lambda b:
inject(Bool(b == 't'))))\
.with_name('bool')
extended_alph_char = choice(letter, oneOf('+-.*/<=>!?:$%_&~^'))
char = string('#\\').skip(
letter.bind(lambda c:
inject(Char(c)))) \
.with_name('char')
nil = string('()').skip(
pc.inject(empty_list)).with_name('nil')
immediate = choice(fixnum, char, bool, nil).with_name('immediate')
class _expr(pc.Parser):
name = '_expr'
def parse(self,s):
return pc.choice(immediate, primitive, conditional, logical).parse(s)
expr = _expr().drop_whitespace().with_name('expr')
