def print_grammar(grammar_txt, grammar_fname):
g_parser = HandRolledGrammarParser(grammar_txt, grammar_fname)
g_ast, err = g_parser.parse()
if err:
return None, err
g, _ = Analyzer(g_ast).analyze()
printer = GrammarPrinter(g)
return printer.parse()
def print_grammar(grammar_txt, grammar_fname):
g_parser = HandRolledGrammarParser(grammar_txt, grammar_fname)
g_ast, err = g_parser.parse()
if err:
return None, err
g, _ = Analyzer(g_ast).analyze()
printer = GrammarPrinter(g)
return printer.parse()
def __init__(self, grammar, classname, package, inline_base):
self.grammar = grammar
self.classname = classname
self.package = package
self.inline_base = inline_base
self.printer = GrammarPrinter(grammar)
self.val = None
self.err = None
self.indent = 0
self.shiftwidth = 4
self.istr = ' ' * self.shiftwidth
class Compiler(object):
def __init__(self, grammar, classname, package, inline_base):
self.grammar = grammar
self.classname = classname
self.package = package
self.inline_base = inline_base
self.printer = GrammarPrinter(grammar)
self.val = None
self.err = None
self.indent = 0
self.shiftwidth = 4
self.istr = ' ' * self.shiftwidth
def walk(self):
self.val = []
if self.inline_base:
self._ext(self.inline_base)
else:
if self.package:
from_cls = "%s.compiled_parser_base" % (self.package)
else:
from_cls = "compiled_parser_base"
self._ext('from %s import CompiledParserBase' % from_cls)
self._ext('',
'',
'class %s(CompiledParserBase):' % self.classname)
for rule_name, node in self.grammar.rules.items():
docstring = self.printer._proc(node)
self._indent()
self._ext('',
'def _%s_(self):' % rule_name)
self._indent()
self._ext('""" %s """' % docstring)
self._proc(node)
self._dedent()
self._dedent()
if self.err:
return None, self.err
return '\n'.join(v.rstrip() for v in self.val) + '\n', None
def _nyi(self, label):
self._ext("# nyi - %s" % label)
def _indent(self):
self.indent += 1
def _dedent(self):
self.indent -= 1
def _ext(self, *lines):
for l in lines:
self.val.append('%s%s' % (' ' * self.indent * self.shiftwidth, l))
def _proc(self, node):
node_type = node[0]
fn = getattr(self, '_' + node_type + '_', None)
if not fn:
import pdb; pdb.set_trace()
return fn(node)
def _choice_(self, node):
if len(node[1]) == 1:
self._proc(node[1][0])
return
self._ext('p = self.pos')
for i, choice in enumerate(node[1]):
self._ext('def choice_%d():' % i)
self._indent()
self._proc(choice)
self._dedent()
self._ext('choice_%d()' % i)
if i < len(node[1]) - 1:
self._ext('if not self.err:',
self.istr + 'return',
'')
self._ext('self.pos = p')
def _seq_(self, node):
for i, s in enumerate(node[1]):
self._proc(s)
if i < len(node[1]) - 1:
self._ext('if self.err:',
self.istr + 'return')
def _label_(self, node):
self._proc(node[1])
self._ext('if not self.err:',
self.istr + 'v_%s = self.val' % node[2])
def _post_(self, node):
if node[2] == '?':
self._proc(node[1])
self._ext('self.err = None')
return
self._ext('vs = []')
if node[2] == '+':
self._proc(node[1])
self._ext('if self.err:',
self.istr + 'return')
self._ext('vs.append(self.val)')
self._ext("while not self.err:")
self._indent()
self._proc(node[1])
self._ext('if not self.err:',
self.istr + 'vs.append(self.val)')
self._dedent()
self._ext('self.val = vs',
'self.err = None')
def _apply_(self, node):
self._ext('self._%s_()' % node[1])
def _action_(self, node):
self._ext('self.val = %s' % self._proc(node[1]),
'self.err = None')
def _not_(self, node):
self._ext('p = self.pos')
self._proc(node[1])
self._ext('self.pos = p')
self._ext('if not self.err:',
self.istr + ' self.err = "not"',
self.istr + ' self.val = None',
self.istr + ' return',
'self.err = None')
def _pred_(self, _node):
self._ext('v = %s' % self._proc(node(1)),
'if v:',
self.istr + 'self.val = v',
self.istr + 'self.err = None',
'else:',
self.istr + 'self.err = "pred check failed"',
self.istr + 'self.val = None')
def _lit_(self, node):
self._ext("self._expect('%s')" % node[1].replace("'", "\\'"))
def _paren_(self, node):
self._ext('def group():')
self._indent()
self._proc(node[1])
self._dedent()
self._ext('group()')
def _py_plus_(self, node):
return '%s + %s' % (self._proc(node[1]), self._proc(node[2]))
def _py_qual_(self, node):
v = self._proc(node[1])
for p in node[2]:
v += self._proc(p)
return v
def _py_getitem_(self, node):
return '[' + str(self._proc(node[1])) + ']'
def _py_getattr_(self, node):
return '.' + node[1]
def _py_call_(self, node):
args = [self._proc(e) for e in node[1]]
return '(' + ', '.join(args) + ')'
def _py_lit_(self, node):
return "'%s'" % node[1].replace("'", "\\'")
def _py_var_(self, node):
return 'v_%s' % node[1]
def _py_num_(self, node):
return node[1]
def _py_arr_(self, node):
return '[' + ', '.join(self._proc(e) for e in node[1]) + ']'