Merged revisions 72924 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r72924 | georg.brandl | 2009-05-25 23:02:56 +0200 (Mo, 25 Mai 2009) | 6 lines
Allow multiple context managers in one with statement, as proposed
in http://codereview.appspot.com/53094 and accepted by Guido.
The construct is transformed into multiple With AST nodes so that
there should be no problems with the semantics.
........
diff --git a/Modules/parsermodule.c b/Modules/parsermodule.c
index 49f6e23..a16e69c 100644
--- a/Modules/parsermodule.c
+++ b/Modules/parsermodule.c
@@ -2446,36 +2446,39 @@
return ok;
}
-/* with_var
-with_var: 'as' expr
+/* with_item:
+ * test ['as' expr]
*/
static int
-validate_with_var(node *tree)
+validate_with_item(node *tree)
{
int nch = NCH(tree);
- int ok = (validate_ntype(tree, with_var)
- && (nch == 2)
- && validate_name(CHILD(tree, 0), "as")
- && validate_expr(CHILD(tree, 1)));
- return ok;
+ int ok = (validate_ntype(tree, with_item)
+ && (nch == 1 || nch == 3)
+ && validate_test(CHILD(tree, 0)));
+ if (ok && nch == 3)
+ ok = (validate_name(CHILD(tree, 1), "as")
+ && validate_expr(CHILD(tree, 2)));
+ return ok;
}
-/* with_stmt
- * 0 1 2 -2 -1
-with_stmt: 'with' test [ with_var ] ':' suite
+/* with_stmt:
+ * 0 1 ... -2 -1
+ * 'with' with_item (',' with_item)* ':' suite
*/
static int
validate_with_stmt(node *tree)
{
+ int i;
int nch = NCH(tree);
int ok = (validate_ntype(tree, with_stmt)
- && ((nch == 4) || (nch == 5))
+ && (nch % 2 == 0)
&& validate_name(CHILD(tree, 0), "with")
- && validate_test(CHILD(tree, 1))
- && (nch == 4 || validate_with_var(CHILD(tree, 2)))
&& validate_colon(RCHILD(tree, -2))
&& validate_suite(RCHILD(tree, -1)));
- return ok;
+ for (i = 1; ok && i < nch - 2; i += 2)
+ ok = validate_with_item(CHILD(tree, i));
+ return ok;
}
/* funcdef: