本文整理汇总了Python中Lexer.Lexer.expect方法的典型用法代码示例。如果您正苦于以下问题：Python Lexer.expect方法的具体用法？Python Lexer.expect怎么用？Python Lexer.expect使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类Lexer.Lexer的用法示例。
在下文中一共展示了Lexer.expect方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: Parser
# 需要导入模块: from Lexer import Lexer [as 别名]
# 或者: from Lexer.Lexer import expect [as 别名]
class Parser(object):
def __init__(self, file=None, stream=None, encoding="utf-8"):
self.lexer = Lexer(file, stream, encoding)
for NodeType in [
AST.Rule,
AST.Define,
AST.Pattern,
AST.Section,
AST.SectionReference
]:
setattr(self, NodeType.__name__, self.create_line_wrapper(NodeType))
self.rules_file = [self.Section('::main::', None)]
def create_line_wrapper(self, NodeType):
"""
Uses reflection to create a version of each task with the line
number of the rules file lexer bound to the constructor
@param NodeType: a Python class to wrap
"""
parent_self = self
class Wrapper(NodeType):
def __init__(self, *args, **kw_args):
NodeType.__init__(self, *args, line_number=parent_self.lexer.line, **kw_args)
Wrapper.__name__ = NodeType.__name__ + 'Wrapper'
return Wrapper
def parse(self):
"""
Parse the rules file into an AST tree
@return: a Section object described by the rules file
"""
self.lexer.skip('whitespace', 'comment', 'newline')
while self.lexer.token != 'end of stream':
self.parse_statement()
self.lexer.skip('whitespace', 'comment', 'newline')
if len(self.rules_file) > 1:
raise RulesFileException("'Section' without 'End Section'")
return self.rules_file.pop()
def parse_statement(self):
"""
Parse parse a single statement in the rules file, and attach it
to the AST object
@return: None
"""
list_is_keyword = lambda x, y: len(x) == 1 and x[0].lower() == y.lower()
id, commands = self.parse_commands_and_id()
self.lexer.skip('whitespace')
if list_is_keyword(commands, 'let'):
# Let ID = PATTERN
self.lexer.expect('equals')
self.lexer.skip('whitespace')
self.parse_definition(id)
elif len(commands) == 0 and id is not None and id.lower() == 'skip':
# Skip: RULE
self.lexer.expect('colon')
self.parse_rule(None, 'skip')
elif list_is_keyword(commands, 'section'):
# Section ID
self.lexer.skip('whitespace')
attributes = self.parse_section_attributes()
inherits = 'inherits' in attributes
exits = 'exits' in attributes
new_section = self.Section(id, self.rules_file[-1], inherits=inherits, exits=exits)
self.rules_file[-1].add_scope('section', new_section)
self.rules_file.append(new_section)
elif list_is_keyword(commands, 'end') and id.lower() == 'section':
# End Section
if len(self.rules_file) < 2:
self.lexer.throw('"End Section" statement when not in a section')
self.rules_file.pop()
else:
# (COMMAND (,COMMAND)*)? ID: RULE
if self.lexer.token in ('colon', 'literalsingle', 'literaldouble'):
self.lexer.expect('colon')
self.parse_rule(id, commands)
self.lexer.skip('whitespace', 'comment')
self.lexer.expect_one_of('newline', 'endofstream')
def parse_commands_and_id(self):
"""
Parse out a list of commands followed by an identifier
@return: tuple with a string of the rule name and a list of commands. If ID is not provided, it is None.
"""
id = self.lexer.expect('identifier')
commands = []
self.lexer.skip('whitespace')
while self.lexer.token == 'comma':
self.lexer.expect('comma')
self.lexer.skip('whitespace')
commands.append(self.lexer.expect('identifier'))
self.lexer.skip('whitespace')
if len(commands) > 0:
commands.insert(0, id)
id = None
if id is None:
id = self.lexer.expect('identifier')
elif self.lexer.token == 'identifier':
#.........这里部分代码省略.........