py/runtime: Implement dispatch for "reverse op" special methods.

If, for class X, X.__add__(Y) doesn't exist (or returns NotImplemented),
try Y.__radd__(X) instead.

This patch could be simpler, but requires undoing operand swap and
operation switch to get non-confusing error message in case __radd__
doesn't exist.
This commit is contained in:
Paul Sokolovsky 2017-09-10 17:05:20 +03:00
parent de981040b3
commit eb84a830df
5 changed files with 48 additions and 2 deletions

View File

@ -35,6 +35,7 @@
#define MICROPY_FLOAT_HIGH_QUALITY_HASH (1)
#define MICROPY_ENABLE_SCHEDULER (1)
#define MICROPY_PY_DELATTR_SETATTR (1)
#define MICROPY_PY_REVERSE_SPECIAL_METHODS (1)
#define MICROPY_PY_BUILTINS_HELP (1)
#define MICROPY_PY_BUILTINS_HELP_MODULES (1)
#define MICROPY_PY_SYS_GETSIZEOF (1)

View File

@ -759,11 +759,19 @@ typedef double mp_float_t;
#endif
// Whether to support complete set of special methods
// for user classes, otherwise only the most used
// for user classes, or only the most used ones. "Reverse"
// methods are controlled by MICROPY_PY_REVERSE_SPECIAL_METHODS
// below.
#ifndef MICROPY_PY_ALL_SPECIAL_METHODS
#define MICROPY_PY_ALL_SPECIAL_METHODS (0)
#endif
// Whether to support reverse arithmetic operarions methods
// (__radd__, etc.)
#ifndef MICROPY_PY_REVERSE_SPECIAL_METHODS
#define MICROPY_PY_REVERSE_SPECIAL_METHODS (0)
#endif
// Whether to support compile function
#ifndef MICROPY_PY_BUILTINS_COMPILE
#define MICROPY_PY_BUILTINS_COMPILE (0)

View File

@ -441,6 +441,13 @@ const qstr mp_binary_op_method_name[] = {
MP_BINARY_OP_INPLACE_TRUE_DIVIDE,
MP_BINARY_OP_INPLACE_MODULO,
MP_BINARY_OP_INPLACE_POWER,*/
#if MICROPY_PY_REVERSE_SPECIAL_METHODS
[MP_BINARY_OP_REVERSE_ADD] = MP_QSTR___radd__,
[MP_BINARY_OP_REVERSE_SUBTRACT] = MP_QSTR___rsub__,
[MP_BINARY_OP_REVERSE_MULTIPLY] = MP_QSTR___rmul__,
#endif
[MP_BINARY_OP_LESS] = MP_QSTR___lt__,
[MP_BINARY_OP_MORE] = MP_QSTR___gt__,
[MP_BINARY_OP_EQUAL] = MP_QSTR___eq__,

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@ -555,7 +555,20 @@ generic_binary_op:
}
}
// TODO implement dispatch for reverse binary ops
#if MICROPY_PY_REVERSE_SPECIAL_METHODS
if (op >= MP_BINARY_OP_OR && op <= MP_BINARY_OP_REVERSE_POWER) {
mp_obj_t t = rhs;
rhs = lhs;
lhs = t;
if (op <= MP_BINARY_OP_POWER) {
op += MP_BINARY_OP_REVERSE_OR - MP_BINARY_OP_OR;
goto generic_binary_op;
}
// Convert __rop__ back to __op__ for error message
op -= MP_BINARY_OP_REVERSE_OR - MP_BINARY_OP_OR;
}
#endif
unsupported_op:
if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {

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@ -101,6 +101,23 @@ typedef enum {
// Operations below this line don't appear in bytecode, they
// just identify special methods.
// MP_BINARY_OP_REVERSE_* must follow immediately after MP_BINARY_OP_*
#if MICROPY_PY_REVERSE_SPECIAL_METHODS
MP_BINARY_OP_REVERSE_OR,
MP_BINARY_OP_REVERSE_XOR,
MP_BINARY_OP_REVERSE_AND,
MP_BINARY_OP_REVERSE_LSHIFT,
MP_BINARY_OP_REVERSE_RSHIFT,
MP_BINARY_OP_REVERSE_ADD,
MP_BINARY_OP_REVERSE_SUBTRACT,
MP_BINARY_OP_REVERSE_MULTIPLY,
MP_BINARY_OP_REVERSE_FLOOR_DIVIDE,
MP_BINARY_OP_REVERSE_TRUE_DIVIDE,
MP_BINARY_OP_REVERSE_MODULO,
MP_BINARY_OP_REVERSE_POWER,
#endif
MP_BINARY_OP_DIVMOD, // not emitted by the compiler but supported by the runtime
MP_BINARY_OP_LAST,