本文整理汇总了Python中scanner.Scanner.showerror方法的典型用法代码示例。如果您正苦于以下问题：Python Scanner.showerror方法的具体用法？Python Scanner.showerror怎么用？Python Scanner.showerror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scanner.Scanner的用法示例。
在下文中一共展示了Scanner.showerror方法的5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: __init__
# 需要导入模块: from scanner import Scanner [as 别名]
# 或者: from scanner.Scanner import showerror [as 别名]
class Parser:
def __init__(self, text=''):
self.lex = Scanner(text) # make a scanner
self.vars = {'pi':3.14159} # add constants
self.traceme = TraceDefault
def parse(self, *text): # external interface
if text:
self.lex.newtext(text[0]) # reuse with new text
tree = self.analyse() # parse string
if tree:
if self.traceme: # dump parse-tree?
print; tree.trace(0)
if self.errorCheck(tree): # check names
self.interpret(tree) # evaluate tree
def analyse(self):
try:
self.lex.scan() # get first token
return self.Goal() # build a parse-tree
except SyntaxError:
print 'Syntax Error at column:', self.lex.start
self.lex.showerror()
except LexicalError:
print 'Lexical Error at column:', self.lex.start
self.lex.showerror()
def errorCheck(self, tree):
try:
tree.validate(self.vars) # error checker
return 'ok'
except UndefinedError, varinfo:
print "'%s' is undefined at column: %d" % varinfo
self.lex.start = varinfo[1]
self.lex.showerror() # returns None 示例2: __init__
# 需要导入模块: from scanner import Scanner [as 别名]
# 或者: from scanner.Scanner import showerror [as 别名]
class Parser:
def __init__(self, text=''):
self.lex = Scanner(text) # embed a scanner
self.vars = {'pi':3.14159} # add a variable
def parse(self, *text):
if text: # main entry-point
self.lex.newtext(text[0]) # reuse this parser?
try:
self.lex.scan() # get first token
self.Goal() # parse a sentence
except SyntaxError:
print 'Syntax Error at column:', self.lex.start
self.lex.showerror()
except LexicalError:
print 'Lexical Error at column:', self.lex.start
self.lex.showerror()
except UndefinedError, name:
print "'%s' is undefined at column:" % name, self.lex.start
self.lex.showerror()示例3: __init__
# 需要导入模块: from scanner import Scanner [as 别名]
# 或者: from scanner.Scanner import showerror [as 别名]
class Parser:
def __init__(self, text=''):
self.lex = Scanner(text) # embed a scanner
self.vars = {'pi': 3.14159} # add a variable
def parse(self, *text):
if text: # main entry-point
self.lex.newtext(text[0]) # reuse this parser?
try:
self.lex.scan() # get first token
self.Goal() # parse a sentence
except SyntaxError:
print('Syntax Error at column:', self.lex.start)
self.lex.showerror()
except LexicalError:
print('Lexical Error at column:', self.lex.start)
self.lex.showerror()
except UndefinedError as E:
name = E.args[0]
print("'%s' is undefined at column:" % name, self.lex.start)
self.lex.showerror()
def Goal(self):
if self.lex.token in ['num', 'var', '(']:
val = self.Expr()
self.lex.match('\0') # expression?
print(val)
elif self.lex.token == 'set': # set command?
self.Assign()
self.lex.match('\0')
else:
raise SyntaxError()
def Assign(self):
self.lex.match('set')
var = self.lex.match('var')
val = self.Expr()
self.vars[var] = val # assign name in dict
def Expr(self):
left = self.Factor()
while True:
if self.lex.token in ['\0', ')']:
return left
elif self.lex.token == '+':
self.lex.scan()
left = left + self.Factor()
elif self.lex.token == '-':
self.lex.scan()
left = left - self.Factor()
else:
raise SyntaxError()
def Factor(self):
left = self.Term()
while True:
if self.lex.token in ['+', '-', '\0', ')']:
return left
elif self.lex.token == '*':
self.lex.scan()
left = left * self.Term()
elif self.lex.token == '/':
self.lex.scan()
left = left / self.Term()
else:
raise SyntaxError()
def Term(self):
if self.lex.token == 'num':
val = self.lex.match('num') # numbers
return val
elif self.lex.token == 'var':
if self.lex.value in self.vars.keys(): # keys(): EIBTI!
val = self.vars[self.lex.value] # look up name's value
self.lex.scan()
return val
else:
raise UndefinedError(self.lex.value)
elif self.lex.token == '(':
self.lex.scan()
val = self.Expr() # sub-expression
self.lex.match(')')
return val
else:
raise SyntaxError()示例4: __init__
# 需要导入模块: from scanner import Scanner [as 别名]
# 或者: from scanner.Scanner import showerror [as 别名]
class Parser:
def __init__(self, text=''):
self.lex = Scanner(text) # make a scanner
self.vars = {'pi':3.14159} # add constants
self.traceme = TraceDefault
def parse(self, *text): # external interface
if text:
self.lex.new_text(text[0]) # reuse with new text
tree = self.analyse() # parse string
if tree:
if self.traceme: # dump parse-tree?
print(); tree.trace(0)
if self.errorCheck(tree): # check names
self.interpret(tree) # evaluate tree
def analyse(self):
try:
self.lex.scan() # get first token
return self.Goal() # build a parse-tree
except SyntaxError:
print('Syntax Error at column:', self.lex.start)
self.lex.showerror()
except LexicalError:
print('Lexical Error at column:', self.lex.start)
self.lex.showerror()
def errorCheck(self, tree):
try:
tree.validate(self.vars) # error checker
return 'ok'
except UndefinedError as instance: # args is a tuple
varinfo = instance.args
print("'%s' is undefined at column: %d" % varinfo)
self.lex.start = varinfo[1]
self.lex.showerror() # returns None
def interpret(self, tree):
result = tree.apply(self.vars) # tree evals itself
if result != None: # ignore 'set' result
print(result) # ignores errors
def Goal(self):
if self.lex.token in ['num', 'var', '(']:
tree = self.Expr()
self.lex.match('\0')
return tree
elif self.lex.token == 'set':
tree = self.Assign()
self.lex.match('\0')
return tree
else:
raise SyntaxError()
def Assign(self):
self.lex.match('set')
vartree = VarNode(self.lex.value, self.lex.start)
self.lex.match('var')
valtree = self.Expr()
return AssignNode(vartree, valtree) # two subtrees
def Expr(self):
left = self.Factor() # left subtree
while True:
if self.lex.token in ['\0', ')']:
return left
elif self.lex.token == '+':
self.lex.scan()
left = PlusNode(left, self.Factor()) # add root-node
elif self.lex.token == '-':
self.lex.scan()
left = MinusNode(left, self.Factor()) # grows up/right
else:
raise SyntaxError()
def Factor(self):
left = self.Term()
while True:
if self.lex.token in ['+', '-', '\0', ')']:
return left
elif self.lex.token == '*':
self.lex.scan()
left = TimesNode(left, self.Term())
elif self.lex.token == '/':
self.lex.scan()
left = DivideNode(left, self.Term())
else:
raise SyntaxError()
def Term(self):
if self.lex.token == 'num':
leaf = NumNode(self.lex.match('num'))
return leaf
elif self.lex.token == 'var':
leaf = VarNode(self.lex.value, self.lex.start)
self.lex.scan()
return leaf
elif self.lex.token == '(':
self.lex.scan()
tree = self.Expr()
#.........这里部分代码省略.........
示例5: __init__
# 需要导入模块: from scanner import Scanner [as 别名]
# 或者: from scanner.Scanner import showerror [as 别名]
class Parser:
def __init__(self, text=""):
self.lex = Scanner(text) # make a scanner
self.vars = {"pi": 3.14159} # add constants
self.traceme = TraceDefault
def parse(self, *text): # external interface
if text:
self.lex.newtext(text[0]) # reuse with new text
tree = self.analyse() # parse string
if tree:
if self.traceme: # dump parse-tree?
print()
tree.trace(0)
if self.errorCheck(tree): # check names
self.interpret(tree) # evaluate tree
def analyse(self):
try:
self.lex.scan() # get first token
return self.Goal() # build a parse-tree
except SyntaxError:
print("Syntax Error at column:", self.lex.start)
self.lex.showerror()
except LexicalError:
print("Lexical Error at column:", self.lex.start)
self.lex.showerror()
def errorCheck(self, tree):
try:
tree.validate(self.vars) # error checker
return "ok"
except UndefinedError as instance: # args is a tuple
varinfo = instance.args
print("'%s' is undefined at column: %d" % varinfo)
self.lex.start = varinfo[1]
self.lex.showerror() # returns None
def interpret(self, tree):
result = tree.apply(self.vars) # tree evals itself
if result != None: # ignore 'set' result
print(result) # ignores errors
def Goal(self):
if self.lex.token in ["num", "var", "("]:
tree = self.Expr()
self.lex.match("\0")
return tree
elif self.lex.token == "set":
tree = self.Assign()
self.lex.match("\0")
return tree
else:
raise SyntaxError()
def Assign(self):
self.lex.match("set")
vartree = VarNode(self.lex.value, self.lex.start)
self.lex.match("var")
valtree = self.Expr()
return AssignNode(vartree, valtree) # two subtrees
def Expr(self):
left = self.Factor() # left subtree
while True:
if self.lex.token in ["\0", ")"]:
return left
elif self.lex.token == "+":
self.lex.scan()
left = PlusNode(left, self.Factor()) # add root-node
elif self.lex.token == "-":
self.lex.scan()
left = MinusNode(left, self.Factor()) # grows up/right
else:
raise SyntaxError()
def Factor(self):
left = self.Term()
while True:
if self.lex.token in ["+", "-", "\0", ")"]:
return left
elif self.lex.token == "*":
self.lex.scan()
left = TimesNode(left, self.Term())
elif self.lex.token == "/":
self.lex.scan()
left = DivideNode(left, self.Term())
else:
raise SyntaxError()
def Term(self):
if self.lex.token == "num":
leaf = NumNode(self.lex.match("num"))
return leaf
elif self.lex.token == "var":
leaf = VarNode(self.lex.value, self.lex.start)
self.lex.scan()
return leaf
elif self.lex.token == "(":
self.lex.scan()
#.........这里部分代码省略.........