Hi,
I'm looking closely at shapes and property trees. I've been using the
dump() and dumpSubtree() methods, among other things, and I'm seeing
some strange things.
Here's some reasonable-looking output:
class Array emptyShape
id "length" g/s 0x7f06ae61fb10/0x7f06ae61fbf0 slot -1 attrs 44
(permanent shared) flags 0 nkids=1
id "toSource" g/s (nil)/(nil) slot 0 attrs 0 flags 0 nkids=1
id "toString" g/s (nil)/(nil) slot 1 attrs 0 flags 0 nkids=1
id "toLocaleString" g/s (nil)/(nil) slot 2 attrs 0 flags 0 nkids=1
id "join" g/s (nil)/(nil) slot 3 attrs 0 flags 0 nkids=1
id "reverse" g/s (nil)/(nil) slot 4 attrs 0 flags 0 nkids=1
id "sort" g/s (nil)/(nil) slot 5 attrs 0 flags 0 nkids=1
id "push" g/s (nil)/(nil) slot 6 attrs 0 flags 0 nkids=1
id "pop" g/s (nil)/(nil) slot 7 attrs 0 flags 0 nkids=1
id "shift" g/s (nil)/(nil) slot 8 attrs 0 flags 0 nkids=1
id "unshift" g/s (nil)/(nil) slot 9 attrs 0 flags 0 nkids=1
We have a property tree for |Array|, and it looks reasonable.
Here's part of a stranger one:
class Array emptyShape
id "length" g/s 0x7f06ae61fb10/0x7f06ae61fbf0 slot -1 attrs 44
(permanent shared) flags 0 nkids=0
id "length" g/s 0x7f06ae61fb10/0x7f06ae61fbf0 slot -1 attrs 44
(permanent shared) flags 0 nkids=1
id "toSource" g/s (nil)/(nil) slot 0 attrs 0 flags 0 nkids=1
id "toString" g/s (nil)/(nil) slot 1 attrs 0 flags 0 nkids=1
id "toLocaleString" g/s (nil)/(nil) slot 2 attrs 0 flags 0 nkids=1
id "join" g/s (nil)/(nil) slot 3 attrs 0 flags 0 nkids=1
id "reverse" g/s (nil)/(nil) slot 4 attrs 0 flags 0 nkids=1
id "sort" g/s (nil)/(nil) slot 5 attrs 0 flags 0 nkids=1
id "push" g/s (nil)/(nil) slot 6 attrs 0 flags 0 nkids=1
id "pop" g/s (nil)/(nil) slot 7 attrs 0 flags 0 nkids=1
Two seemingly identical |length| shapes, both at depth 1. How does that happen?
Here's part of another strange one:
class Function emptyShape
id "length" g/s (nil)/(nil) slot 0 attrs 6 (readonly permanent) flags
0 nkids=1
id "name" g/s (nil)/(nil) slot 1 attrs 6 (readonly permanent) flags 0 nkids=1
id "arguments" g/s 0x7f06ae9175b0/(nil) slot -1 attrs 44 (permanent
shared) flags 0 nkids=2
id "caller" g/s 0x7f06ae9175b0/(nil) slot -1 attrs 44 (permanent
shared) flags 0 nkids=0
id "caller" g/s 0x7f06ae9175b0/(nil) slot -1 attrs 44 (permanent
shared) flags 0 nkids=0
id "join" g/s (nil)/(nil) slot 0 attrs 0 flags 0 nkids=1
id "reverse" g/s (nil)/(nil) slot 1 attrs 0 flags 0 nkids=1
id "sort" g/s (nil)/(nil) slot 2 attrs 0 flags 0 nkids=1
id "push" g/s (nil)/(nil) slot 3 attrs 0 flags 0 nkids=1
id "pop" g/s (nil)/(nil) slot 4 attrs 0 flags 0 nkids=1
id "shift" g/s (nil)/(nil) slot 5 attrs 0 flags 0 nkids=1
id "unshift" g/s (nil)/(nil) slot 6 attrs 0 flags 0 nkids=1
The sub-tree containing |length|, |name|, |arguments| and |caller|
seems reasonable (well, except for the duplication of |caller|). But
the next subtree contains all the Array methods! And this tree goes on
to include additional sub-trees containing methods for typed arrays,
iterators, Math, RegExp, String, Date, and others. How does that
happen?
Thanks.
Nick
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