def eval_condition(self, condition):
# exceptions are handled by the caller
parser = BooleanParser(env, condition, state='variable')
expr = parser.parse_expression()
if not parser.stream.eos:
raise ValueError('chunk after expression')
def eval_node(node):
if isinstance(node, nodes.CondExpr):
if eval_node(node.test):
return eval_node(node.expr1)
else:
return eval_node(node.expr2)
elif isinstance(node, nodes.And):
return eval_node(node.left) and eval_node(node.right)
elif isinstance(node, nodes.Or):
return eval_node(node.left) or eval_node(node.right)
elif isinstance(node, nodes.Not):
return not eval_node(node.node)
elif isinstance(node, nodes.Name):
return self.tags.get(node.name, False)
else:
raise ValueError('invalid node, check parsing')
return eval_node(expr)
python类CondExpr()的实例源码
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1
def parse_condexpr(self):
lineno = self.stream.current.lineno
expr1 = self.parse_or()
while self.stream.skip_if('name:if'):
expr2 = self.parse_or()
if self.stream.skip_if('name:else'):
expr3 = self.parse_condexpr()
else:
expr3 = None
expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
lineno = self.stream.current.lineno
return expr1