diff options
Diffstat (limited to 'Lib/compiler/transformer.py')
| -rw-r--r-- | Lib/compiler/transformer.py | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/Lib/compiler/transformer.py b/Lib/compiler/transformer.py index 9074fc767a..6832cf1003 100644 --- a/Lib/compiler/transformer.py +++ b/Lib/compiler/transformer.py @@ -534,6 +534,12 @@ class Transformer: testlist1 = testlist exprlist = testlist + def testlist_gexp(self, nodelist): + if len(nodelist) == 2 and nodelist[1][0] == symbol.gen_for: + test = self.com_node(nodelist[0]) + return self.com_generator_expression(test, nodelist[1]) + return self.testlist(nodelist) + def test(self, nodelist): # and_test ('or' and_test)* | lambdef if len(nodelist) == 1 and nodelist[0][0] == symbol.lambdef: @@ -1085,6 +1091,48 @@ class Transformer: values.append(self.com_node(nodelist[i])) return List(values) + if hasattr(symbol, 'gen_for'): + def com_generator_expression(self, expr, node): + # gen_iter: gen_for | gen_if + # gen_for: 'for' exprlist 'in' test [gen_iter] + # gen_if: 'if' test [gen_iter] + + lineno = node[1][2] + fors = [] + while node: + t = node[1][1] + if t == 'for': + assignNode = self.com_assign(node[2], OP_ASSIGN) + genNode = self.com_node(node[4]) + newfor = GenExprFor(assignNode, genNode, []) + newfor.lineno = node[1][2] + fors.append(newfor) + if (len(node)) == 5: + node = None + else: + node = self.com_gen_iter(node[5]) + elif t == 'if': + test = self.com_node(node[2]) + newif = GenExprIf(test) + newif.lineno = node[1][2] + newfor.ifs.append(newif) + if len(node) == 3: + node = None + else: + node = self.com_gen_iter(node[3]) + else: + raise SyntaxError, \ + ("unexpected generator expression element: %s %d" + % (node, lineno)) + fors[0].is_outmost = True + n = GenExpr(GenExprInner(expr, fors)) + n.lineno = lineno + return n + + def com_gen_iter(self, node): + assert node[0] == symbol.gen_iter + return node[1] + def com_dictmaker(self, nodelist): # dictmaker: test ':' test (',' test ':' value)* [','] items = [] @@ -1122,6 +1170,8 @@ class Transformer: if node[0] == token.STAR or node[0] == token.DOUBLESTAR: break kw, result = self.com_argument(node, kw) + if len_nodelist != 2 and isinstance(result, GenExpr): + raise SyntaxError, 'generator expression needs parenthesis' args.append(result) else: # No broken by star arg, so skip the last one we processed. @@ -1148,6 +1198,9 @@ class Transformer: return CallFunc(primaryNode, args, star_node, dstar_node) def com_argument(self, nodelist, kw): + if len(nodelist) == 3 and nodelist[2][0] == symbol.gen_for: + test = self.com_node(nodelist[1]) + return 0, self.com_generator_expression(test, nodelist[2]) if len(nodelist) == 2: if kw: raise SyntaxError, "non-keyword arg after keyword arg" |