simplify visitor walker class
- remove postorder - remove protocol for automatically walking children based on visitor method return value; now only walks if there is no method
This commit is contained in:
Jeremy Hylton
parent
b631b8ede5
commit
f635abee3a
|
|
@ -47,31 +47,19 @@ class ASTVisitor:
|
|||
self._preorder(tree)
|
||||
|
||||
def _preorder(self, node, *args):
|
||||
stop = apply(self.dispatch, (node,) + args)
|
||||
if stop:
|
||||
return
|
||||
return apply(self.dispatch, (node,) + args)
|
||||
|
||||
def default(self, node, *args):
|
||||
for child in node.getChildren():
|
||||
if isinstance(child, ast.Node):
|
||||
self._preorder(child)
|
||||
|
||||
def postorder(self, tree, visitor):
|
||||
"""Do preorder walk of tree using visitor"""
|
||||
self.visitor = visitor
|
||||
visitor.visit = self._postorder
|
||||
self._postorder(tree)
|
||||
|
||||
def _postorder(self, tree, *args):
|
||||
for child in node.getChildren():
|
||||
if isinstance(child, ast.Node):
|
||||
self._postorder(child)
|
||||
apply(self.dispatch, (node,) + args)
|
||||
apply(self._preorder, (child,) + args)
|
||||
|
||||
def dispatch(self, node, *args):
|
||||
self.node = node
|
||||
meth = self._cache.get(node.__class__, None)
|
||||
className = node.__class__.__name__
|
||||
if meth is None:
|
||||
meth = getattr(self.visitor, 'visit' + className, 0)
|
||||
meth = getattr(self.visitor, 'visit' + className, self.default)
|
||||
self._cache[node.__class__] = meth
|
||||
if self.VERBOSE > 0:
|
||||
if self.VERBOSE == 1:
|
||||
|
|
@ -79,8 +67,7 @@ class ASTVisitor:
|
|||
print "dispatch", className
|
||||
else:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
if meth:
|
||||
return apply(meth, (node,) + args)
|
||||
return apply(meth, (node,) + args)
|
||||
|
||||
class ExampleASTVisitor(ASTVisitor):
|
||||
"""Prints examples of the nodes that aren't visited
|
||||
|
|
@ -93,24 +80,27 @@ class ExampleASTVisitor(ASTVisitor):
|
|||
|
||||
def dispatch(self, node, *args):
|
||||
self.node = node
|
||||
className = node.__class__.__name__
|
||||
meth = getattr(self.visitor, 'visit' + className, None)
|
||||
if self.VERBOSE > 0:
|
||||
if self.VERBOSE > 1:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
meth = self._cache.get(node.__class__, None)
|
||||
className = node.__class__.__name__
|
||||
if meth is None:
|
||||
meth = getattr(self.visitor, 'visit' + className, 0)
|
||||
self._cache[node.__class__] = meth
|
||||
if self.VERBOSE > 1:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
if meth:
|
||||
return apply(meth, (node,) + args)
|
||||
elif self.VERBOSE > 0:
|
||||
klass = node.__class__
|
||||
if self.examples.has_key(klass):
|
||||
return
|
||||
self.examples[klass] = klass
|
||||
print
|
||||
print klass
|
||||
for attr in dir(node):
|
||||
if attr[0] != '_':
|
||||
print "\t", "%-12.12s" % attr, getattr(node, attr)
|
||||
print
|
||||
if not self.examples.has_key(klass):
|
||||
self.examples[klass] = klass
|
||||
print
|
||||
print self.visitor
|
||||
print klass
|
||||
for attr in dir(node):
|
||||
if attr[0] != '_':
|
||||
print "\t", "%-12.12s" % attr, getattr(node, attr)
|
||||
print
|
||||
return apply(self.default, (node,) + args)
|
||||
|
||||
_walker = ASTVisitor
|
||||
def walk(tree, visitor, verbose=None):
|
||||
|
|
|
|||
|
|
@ -47,31 +47,19 @@ class ASTVisitor:
|
|||
self._preorder(tree)
|
||||
|
||||
def _preorder(self, node, *args):
|
||||
stop = apply(self.dispatch, (node,) + args)
|
||||
if stop:
|
||||
return
|
||||
return apply(self.dispatch, (node,) + args)
|
||||
|
||||
def default(self, node, *args):
|
||||
for child in node.getChildren():
|
||||
if isinstance(child, ast.Node):
|
||||
self._preorder(child)
|
||||
|
||||
def postorder(self, tree, visitor):
|
||||
"""Do preorder walk of tree using visitor"""
|
||||
self.visitor = visitor
|
||||
visitor.visit = self._postorder
|
||||
self._postorder(tree)
|
||||
|
||||
def _postorder(self, tree, *args):
|
||||
for child in node.getChildren():
|
||||
if isinstance(child, ast.Node):
|
||||
self._postorder(child)
|
||||
apply(self.dispatch, (node,) + args)
|
||||
apply(self._preorder, (child,) + args)
|
||||
|
||||
def dispatch(self, node, *args):
|
||||
self.node = node
|
||||
meth = self._cache.get(node.__class__, None)
|
||||
className = node.__class__.__name__
|
||||
if meth is None:
|
||||
meth = getattr(self.visitor, 'visit' + className, 0)
|
||||
meth = getattr(self.visitor, 'visit' + className, self.default)
|
||||
self._cache[node.__class__] = meth
|
||||
if self.VERBOSE > 0:
|
||||
if self.VERBOSE == 1:
|
||||
|
|
@ -79,8 +67,7 @@ class ASTVisitor:
|
|||
print "dispatch", className
|
||||
else:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
if meth:
|
||||
return apply(meth, (node,) + args)
|
||||
return apply(meth, (node,) + args)
|
||||
|
||||
class ExampleASTVisitor(ASTVisitor):
|
||||
"""Prints examples of the nodes that aren't visited
|
||||
|
|
@ -93,24 +80,27 @@ class ExampleASTVisitor(ASTVisitor):
|
|||
|
||||
def dispatch(self, node, *args):
|
||||
self.node = node
|
||||
className = node.__class__.__name__
|
||||
meth = getattr(self.visitor, 'visit' + className, None)
|
||||
if self.VERBOSE > 0:
|
||||
if self.VERBOSE > 1:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
meth = self._cache.get(node.__class__, None)
|
||||
className = node.__class__.__name__
|
||||
if meth is None:
|
||||
meth = getattr(self.visitor, 'visit' + className, 0)
|
||||
self._cache[node.__class__] = meth
|
||||
if self.VERBOSE > 1:
|
||||
print "dispatch", className, (meth and meth.__name__ or '')
|
||||
if meth:
|
||||
return apply(meth, (node,) + args)
|
||||
elif self.VERBOSE > 0:
|
||||
klass = node.__class__
|
||||
if self.examples.has_key(klass):
|
||||
return
|
||||
self.examples[klass] = klass
|
||||
print
|
||||
print klass
|
||||
for attr in dir(node):
|
||||
if attr[0] != '_':
|
||||
print "\t", "%-12.12s" % attr, getattr(node, attr)
|
||||
print
|
||||
if not self.examples.has_key(klass):
|
||||
self.examples[klass] = klass
|
||||
print
|
||||
print self.visitor
|
||||
print klass
|
||||
for attr in dir(node):
|
||||
if attr[0] != '_':
|
||||
print "\t", "%-12.12s" % attr, getattr(node, attr)
|
||||
print
|
||||
return apply(self.default, (node,) + args)
|
||||
|
||||
_walker = ASTVisitor
|
||||
def walk(tree, visitor, verbose=None):
|
||||
|
|
|
|||
Loading…
Reference in New Issue