def decorator(self, nodelist):
# '@' dotted_name [ '(' [arglist] ')' ]
assert len(nodelist) in (3, 5, 6)
assert nodelist[0][0] == token.AT
assert nodelist[-1][0] == token.NEWLINE
assert nodelist[1][0] == symbol.dotted_name
funcname = self.decorator_name(nodelist[1][1:])
if len(nodelist) > 3:
assert nodelist[2][0] == token.LPAR
expr = self.com_call_function(funcname, nodelist[3])
else:
expr = funcname
return expr
python类expr()的实例源码
def __new__(cls,
name,
expr,
replace = False):
# code
efound = expr in [Variable.variables[key].expr for key in Variable.variables]
if efound:
key = [key for key in Variable.variables if expr in Variable.variables[key].expr]
logger.info("Expression '%s' already exists for key %s", expr, key)
return
else:
if replace or not name in Variable.variables:
if not valid_name(name):
logger.info("Invalid variable key: %s", name)
return
try:
result = parser.expr(expr)
except:
logger.info("Invalid expression: %s", expr)
return
return super(Variable, cls).__new__(cls)
else:
logger.info("Key %s already exists", name)
# function __init__
def decorator(self, nodelist):
# '@' dotted_name [ '(' [arglist] ')' ]
assert len(nodelist) in (3, 5, 6)
assert nodelist[0][0] == token.AT
assert nodelist[-1][0] == token.NEWLINE
assert nodelist[1][0] == symbol.dotted_name
funcname = self.decorator_name(nodelist[1][1:])
if len(nodelist) > 3:
assert nodelist[2][0] == token.LPAR
expr = self.com_call_function(funcname, nodelist[3])
else:
expr = funcname
return expr
def decorator(self, nodelist):
# '@' dotted_name [ '(' [arglist] ')' ]
assert len(nodelist) in (3, 5, 6)
assert nodelist[0][0] == token.AT
assert nodelist[-1][0] == token.NEWLINE
assert nodelist[1][0] == symbol.dotted_name
funcname = self.decorator_name(nodelist[1][1:])
if len(nodelist) > 3:
assert nodelist[2][0] == token.LPAR
expr = self.com_call_function(funcname, nodelist[3])
else:
expr = funcname
return expr
def decorator(self, nodelist):
# '@' dotted_name [ '(' [arglist] ')' ]
assert len(nodelist) in (3, 5, 6)
assert nodelist[0][0] == token.AT
assert nodelist[-1][0] == token.NEWLINE
assert nodelist[1][0] == symbol.dotted_name
funcname = self.decorator_name(nodelist[1][1:])
if len(nodelist) > 3:
assert nodelist[2][0] == token.LPAR
expr = self.com_call_function(funcname, nodelist[3])
else:
expr = funcname
return expr
def decorator(self, nodelist):
# '@' dotted_name [ '(' [arglist] ')' ]
assert len(nodelist) in (3, 5, 6)
assert nodelist[0][0] == token.AT
assert nodelist[-1][0] == token.NEWLINE
assert nodelist[1][0] == symbol.dotted_name
funcname = self.decorator_name(nodelist[1][1:])
if len(nodelist) > 3:
assert nodelist[2][0] == token.LPAR
expr = self.com_call_function(funcname, nodelist[3])
else:
expr = funcname
return expr
def __contains__(self, expr):
"""Implement membership test operator.
Return true if expr matches a packet in the trace file,
false otherwise.
The packet is also stored in the object attribute pkt.
Examples:
# Find the next READ request
if ("NFS.argop == 25" in x):
print x.pkt.nfs
See match() method for more information
"""
pkt = self.match(expr)
return (pkt is not None)
def _match(self, layer, uargs):
"""Default match function."""
if not hasattr(self.pkt, layer):
return False
if layer == "nfs":
# Use special matching function for NFS
texpr = self.match_nfs(uargs)
else:
# Use general match
obj = "self.pkt.%s." % layer.lower()
lhs, opr, rhs = self._split_match(uargs)
expr = self._process_match(obj, lhs, opr, rhs)
texpr = eval(expr)
self.dprint('PKT2', " %d: match_%s(%s) -> %r" % (self.pkt.record.index, layer, uargs, texpr))
return texpr
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented
on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented
on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented
on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def parseexpr(self, text):
"""Return a modified parse tree for the given expression text."""
return self.transform(parser.expr(text))
def yield_stmt(self, nodelist):
expr = self.com_node(nodelist[0])
return Discard(expr, lineno=expr.lineno)
def exec_stmt(self, nodelist):
# exec_stmt: 'exec' expr ['in' expr [',' expr]]
expr1 = self.com_node(nodelist[1])
if len(nodelist) >= 4:
expr2 = self.com_node(nodelist[3])
if len(nodelist) >= 6:
expr3 = self.com_node(nodelist[5])
else:
expr3 = None
else:
expr2 = expr3 = None
return Exec(expr1, expr2, expr3, lineno=nodelist[0][2])
def comparison(self, nodelist):
# comparison: expr (comp_op expr)*
node = self.com_node(nodelist[0])
if len(nodelist) == 1:
return node
results = []
for i in range(2, len(nodelist), 2):
nl = nodelist[i-1]
# comp_op: '<' | '>' | '=' | '>=' | '<=' | '<>' | '!=' | '=='
# | 'in' | 'not' 'in' | 'is' | 'is' 'not'
n = nl[1]
if n[0] == token.NAME:
type = n[1]
if len(nl) == 3:
if type == 'not':
type = 'not in'
else:
type = 'is not'
else:
type = _cmp_types[n[0]]
lineno = nl[1][2]
results.append((type, self.com_node(nodelist[i])))
# we need a special "compare" node so that we can distinguish
# 3 < x < 5 from (3 < x) < 5
# the two have very different semantics and results (note that the
# latter form is always true)
return Compare(node, results, lineno=lineno)
def expr(self, nodelist):
# xor_expr ('|' xor_expr)*
return self.com_binary(Bitor, nodelist)
def com_try_except_finally(self, nodelist):
# ('try' ':' suite
# ((except_clause ':' suite)+ ['else' ':' suite] ['finally' ':' suite]
# | 'finally' ':' suite))
if nodelist[3][0] == token.NAME:
# first clause is a finally clause: only try-finally
return TryFinally(self.com_node(nodelist[2]),
self.com_node(nodelist[5]),
lineno=nodelist[0][2])
#tryexcept: [TryNode, [except_clauses], elseNode)]
clauses = []
elseNode = None
finallyNode = None
for i in range(3, len(nodelist), 3):
node = nodelist[i]
if node[0] == symbol.except_clause:
# except_clause: 'except' [expr [(',' | 'as') expr]] */
if len(node) > 2:
expr1 = self.com_node(node[2])
if len(node) > 4:
expr2 = self.com_assign(node[4], OP_ASSIGN)
else:
expr2 = None
else:
expr1 = expr2 = None
clauses.append((expr1, expr2, self.com_node(nodelist[i+2])))
if node[0] == token.NAME:
if node[1] == 'else':
elseNode = self.com_node(nodelist[i+2])
elif node[1] == 'finally':
finallyNode = self.com_node(nodelist[i+2])
try_except = TryExcept(self.com_node(nodelist[2]), clauses, elseNode,
lineno=nodelist[0][2])
if finallyNode:
return TryFinally(try_except, finallyNode, lineno=nodelist[0][2])
else:
return try_except
def com_with_item(self, nodelist, body, lineno):
# with_item: test ['as' expr]
if len(nodelist) == 4:
var = self.com_assign(nodelist[3], OP_ASSIGN)
else:
var = None
expr = self.com_node(nodelist[1])
return With(expr, var, body, lineno=lineno)
def com_list_comprehension(self, expr, node):
return self.com_comprehension(expr, None, node, 'list')
def com_dictorsetmaker(self, nodelist):
# dictorsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) |
# (test (comp_for | (',' test)* [','])) )
assert nodelist[0] == symbol.dictorsetmaker
nodelist = nodelist[1:]
if len(nodelist) == 1 or nodelist[1][0] == token.COMMA:
# set literal
items = []
for i in range(0, len(nodelist), 2):
items.append(self.com_node(nodelist[i]))
return Set(items, lineno=items[0].lineno)
elif nodelist[1][0] == symbol.comp_for:
# set comprehension
expr = self.com_node(nodelist[0])
return self.com_comprehension(expr, None, nodelist[1], 'set')
elif len(nodelist) > 3 and nodelist[3][0] == symbol.comp_for:
# dict comprehension
assert nodelist[1][0] == token.COLON
key = self.com_node(nodelist[0])
value = self.com_node(nodelist[2])
return self.com_comprehension(key, value, nodelist[3], 'dict')
else:
# dict literal
items = []
for i in range(0, len(nodelist), 4):
items.append((self.com_node(nodelist[i]),
self.com_node(nodelist[i+2])))
return Dict(items, lineno=items[0][0].lineno)
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented
on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented
on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def evaluate_marker(cls, text, extra=None):
"""
Evaluate a PEP 426 environment marker on CPython 2.4+.
Return a boolean indicating the marker result in this environment.
Raise SyntaxError if marker is invalid.
This implementation uses the 'parser' module, which is not implemented on
Jython and has been superseded by the 'ast' module in Python 2.6 and
later.
"""
return cls.interpret(parser.expr(text).totuple(1)[1])
def __init__(self,
name,
expr,
replace = False):
# code
self.name = name;
self.expr = expr;
# add key with expression
Variable.variables[name] = self
# function __str__
def __str__(self):
return self.expr
#
# Function vparse
#
def allvars(expr):
r"""Get the list of valid names in the expression.
Parameters
----------
expr : str
A valid expression conforming to the Variable Definition Language.
Returns
-------
vlist : list
List of valid variable names.
"""
regex = re.compile('\w+')
items = regex.findall(expr)
vlist = []
for item in items:
if valid_name(item):
vlist.append(item)
return vlist
#
# Function vtree
#
