diff options
Diffstat (limited to 'Lib/compiler/symbols.py')
| -rw-r--r-- | Lib/compiler/symbols.py | 44 |
1 files changed, 35 insertions, 9 deletions
diff --git a/Lib/compiler/symbols.py b/Lib/compiler/symbols.py index 40fd127bfd..946a8b1a3a 100644 --- a/Lib/compiler/symbols.py +++ b/Lib/compiler/symbols.py @@ -25,6 +25,7 @@ class Scope: # nested is true if the class could contain free variables, # i.e. if it is nested within another function. self.nested = None + self.generator = None self.klass = None if klass is not None: for i in range(len(klass)): @@ -287,6 +288,27 @@ class SymbolVisitor: name = name[:i] scope.add_def(asname or name) + def visitGlobal(self, node, scope): + for name in node.names: + scope.add_global(name) + + def visitAssign(self, node, scope): + """Propagate assignment flag down to child nodes. + + The Assign node doesn't itself contains the variables being + assigned to. Instead, the children in node.nodes are visited + with the assign flag set to true. When the names occur in + those nodes, they are marked as defs. + + Some names that occur in an assignment target are not bound by + the assignment, e.g. a name occurring inside a slice. The + visitor handles these nodes specially; they do not propagate + the assign flag to their children. + """ + for n in node.nodes: + self.visit(n, scope, 1) + self.visit(node.expr, scope) + def visitAssName(self, node, scope, assign=1): scope.add_def(node.name) @@ -297,6 +319,13 @@ class SymbolVisitor: self.visit(node.expr, scope, 0) for n in node.subs: self.visit(n, scope, 0) + + def visitSlice(self, node, scope, assign=0): + self.visit(node.expr, scope, assign) + if node.lower: + self.visit(node.lower, scope, 0) + if node.upper: + self.visit(node.upper, scope, 0) def visitAugAssign(self, node, scope): # If the LHS is a name, then this counts as assignment. @@ -306,15 +335,6 @@ class SymbolVisitor: self.visit(node.node, scope, 1) # XXX worry about this self.visit(node.expr, scope) - def visitAssign(self, node, scope): - for n in node.nodes: - self.visit(n, scope, 1) - self.visit(node.expr, scope) - - def visitGlobal(self, node, scope): - for name in node.names: - scope.add_global(name) - # prune if statements if tests are false _const_types = types.StringType, types.IntType, types.FloatType @@ -330,6 +350,12 @@ class SymbolVisitor: if node.else_: self.visit(node.else_, scope) + # a yield statement signals a generator + + def visitYield(self, node, scope): + self.generator = 1 + self.visit(node.value, scope) + def sort(l): l = l[:] l.sort() |