From 0705f66eb369aa6a6cdb699e24ff61e1ab2e0c56 Mon Sep 17 00:00:00 2001 From: Ivan Levkivskyi Date: Fri, 3 Mar 2017 22:46:39 +0100 Subject: [PATCH] bpo-26213: Document _UNPACK bytecodes and BUILD_MAP changes (#238) --- Doc/library/dis.rst | 55 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 53 insertions(+), 2 deletions(-) diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst index 694d5642fb..a15ecdcdb9 100644 --- a/Doc/library/dis.rst +++ b/Doc/library/dis.rst @@ -772,8 +772,13 @@ All of the following opcodes use their arguments. .. opcode:: BUILD_MAP (count) - Pushes a new dictionary object onto the stack. The dictionary is pre-sized - to hold *count* entries. + Pushes a new dictionary object onto the stack. Pops ``2 * count`` items + so that the dictionary holds *count* entries: + ``{..., TOS3: TOS2, TOS1: TOS}``. + + .. versionchanged:: 3.5 + The dictionary is created from stack items instead of creating an + empty dictionary pre-sized to hold *count* items. .. opcode:: BUILD_CONST_KEY_MAP (count) @@ -793,6 +798,52 @@ All of the following opcodes use their arguments. .. versionadded:: 3.6 +.. opcode:: BUILD_TUPLE_UNPACK (count) + + Pops *count* iterables from the stack, joins them in a single tuple, + and pushes the result. Implements iterable unpacking in tuple + displays ``(*x, *y, *z)``. + + .. versionadded:: 3.5 + + +.. opcode:: BUILD_LIST_UNPACK (count) + + This is similar to :opcode:`BUILD_TUPLE_UNPACK`, but pushes a list + instead of tuple. Implements iterable unpacking in list + displays ``[*x, *y, *z]``. + + .. versionadded:: 3.5 + + +.. opcode:: BUILD_SET_UNPACK (count) + + This is similar to :opcode:`BUILD_TUPLE_UNPACK`, but pushes a set + instead of tuple. Implements iterable unpacking in set + displays ``{*x, *y, *z}``. + + .. versionadded:: 3.5 + + +.. opcode:: BUILD_MAP_UNPACK (count) + + Pops *count* mappings from the stack, merges them into a single dictionary, + and pushes the result. Implements dictionary unpacking in dictionary + displays ``{**x, **y, **z}``. + + .. versionadded:: 3.5 + + +.. opcode:: BUILD_MAP_UNPACK_WITH_CALL (oparg) + + This is similar to :opcode:`BUILD_MAP_UNPACK`, + but is used for ``f(**x, **y, **z)`` call syntax. The lowest byte of + *oparg* is the count of mappings, the relative position of the + corresponding callable ``f`` is encoded in the second byte of *oparg*. + + .. versionadded:: 3.5 + + .. opcode:: LOAD_ATTR (namei) Replaces TOS with ``getattr(TOS, co_names[namei])``. -- 2.40.0