py/obj.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the Micro Python project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2013, 2014 Damien P. George
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #include <stdint.h>
 #include <stdio.h>
 #include <stdarg.h>
 #include <assert.h>

 #include "mpconfig.h"
 #include "nlr.h"
 #include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "objtype.h"
 #include "mpz.h"
 #include "objint.h"
 #include "runtime0.h"
 #include "runtime.h"
 #include "stackctrl.h"

 mp_obj_type_t *mp_obj_get_type(mp_const_obj_t o_in) {
     if (MP_OBJ_IS_SMALL_INT(o_in)) {
         return (mp_obj_t)&mp_type_int;
     } else if (MP_OBJ_IS_QSTR(o_in)) {
         return (mp_obj_t)&mp_type_str;
     } else {
         const mp_obj_base_t *o = o_in;
         return (mp_obj_t)o->type;
     }
 }

 const char *mp_obj_get_type_str(mp_const_obj_t o_in) {
     return qstr_str(mp_obj_get_type(o_in)->name);
 }

 void printf_wrapper(void *env, const char *fmt, ...) {
     va_list args;
     va_start(args, fmt);
     vprintf(fmt, args);
     va_end(args);
 }

 void mp_obj_print_helper(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t o_in, mp_print_kind_t kind) {
     // There can be data structures nested too deep, or just recursive
     MP_STACK_CHECK();
 #if !NDEBUG
     if (o_in == NULL) {
         print(env, "(nil)");
         return;
     }
 #endif
     mp_obj_type_t *type = mp_obj_get_type(o_in);
     if (type->print != NULL) {
         type->print(print, env, o_in, kind);
     } else {
         print(env, "<%s>", qstr_str(type->name));
     }
 }

 void mp_obj_print(mp_obj_t o_in, mp_print_kind_t kind) {
     mp_obj_print_helper(printf_wrapper, NULL, o_in, kind);
 }

 // helper function to print an exception with traceback
 void mp_obj_print_exception(mp_obj_t exc) {
     if (mp_obj_is_exception_instance(exc)) {
         mp_uint_t n, *values;
         mp_obj_exception_get_traceback(exc, &n, &values);
         if (n > 0) {
             assert(n % 3 == 0);
             printf("Traceback (most recent call last):\n");
             for (int i = n - 3; i >= 0; i -= 3) {
 #if MICROPY_ENABLE_SOURCE_LINE
                 printf("  File \"%s\", line %d", qstr_str(values[i]), (int)values[i + 1]);
 #else
                 printf("  File \"%s\"", qstr_str(values[i]));
 #endif
                 // the block name can be NULL if it's unknown
                 qstr block = values[i + 2];
                 if (block == MP_QSTR_NULL) {
                     printf("\n");
                 } else {
                     printf(", in %s\n", qstr_str(block));
                 }
             }
         }
     }
     mp_obj_print(exc, PRINT_EXC);
     printf("\n");
 }

 bool mp_obj_is_true(mp_obj_t arg) {
     if (arg == mp_const_false) {
         return 0;
     } else if (arg == mp_const_true) {
         return 1;
     } else if (arg == mp_const_none) {
         return 0;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         if (MP_OBJ_SMALL_INT_VALUE(arg) == 0) {
             return 0;
         } else {
             return 1;
         }
     } else {
         mp_obj_type_t *type = mp_obj_get_type(arg);
         if (type->unary_op != NULL) {
             mp_obj_t result = type->unary_op(MP_UNARY_OP_BOOL, arg);
             if (result != MP_OBJ_NULL) {
                 return result == mp_const_true;
             }
         }

         mp_obj_t len = mp_obj_len_maybe(arg);
         if (len != MP_OBJ_NULL) {
             // obj has a length, truth determined if len != 0
             return len != MP_OBJ_NEW_SMALL_INT(0);
         } else {
             // any other obj is true per Python semantics
             return 1;
         }
     }
 }

 bool mp_obj_is_callable(mp_obj_t o_in) {
     mp_call_fun_t call = mp_obj_get_type(o_in)->call;
     if (call != mp_obj_instance_call) {
         return call != NULL;
     }
     return mp_obj_instance_is_callable(o_in);
 }

 mp_int_t mp_obj_hash(mp_obj_t o_in) {
     if (o_in == mp_const_false) {
         return 0; // needs to hash to same as the integer 0, since False==0
     } else if (o_in == mp_const_true) {
         return 1; // needs to hash to same as the integer 1, since True==1
     } else if (MP_OBJ_IS_SMALL_INT(o_in)) {
         return MP_OBJ_SMALL_INT_VALUE(o_in);
     } else if (MP_OBJ_IS_TYPE(o_in, &mp_type_int)) {
         return mp_obj_int_hash(o_in);
     } else if (MP_OBJ_IS_STR(o_in) || MP_OBJ_IS_TYPE(o_in, &mp_type_bytes)) {
         return mp_obj_str_get_hash(o_in);
     } else if (MP_OBJ_IS_TYPE(o_in, &mp_type_NoneType)) {
         return (mp_int_t)o_in;
     } else if (MP_OBJ_IS_FUN(o_in)) {
         return (mp_int_t)o_in;
     } else if (MP_OBJ_IS_TYPE(o_in, &mp_type_tuple)) {
         return mp_obj_tuple_hash(o_in);
     } else if (MP_OBJ_IS_TYPE(o_in, &mp_type_type)) {
         return (mp_int_t)o_in;

     // TODO hash class and instances
     // TODO delegate to __hash__ method if it exists

     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "unhashable type: '%s'", mp_obj_get_type_str(o_in)));
     }
 }

 // this function implements the '==' operator (and so the inverse of '!=')
 // from the python language reference:
 // "The objects need not have the same type. If both are numbers, they are converted
 // to a common type. Otherwise, the == and != operators always consider objects of
 // different types to be unequal."
 // note also that False==0 and True==1 are true expressions
 bool mp_obj_equal(mp_obj_t o1, mp_obj_t o2) {
     if (o1 == o2) {
         return true;
     }
     if (o1 == mp_const_none || o2 == mp_const_none) {
         return false;
     }

     // fast path for small ints
     if (MP_OBJ_IS_SMALL_INT(o1)) {
         if (MP_OBJ_IS_SMALL_INT(o2)) {
             // both SMALL_INT, and not equal if we get here
             return false;
         } else {
             mp_obj_t temp = o2; o2 = o1; o1 = temp;
             // o2 is now the SMALL_INT, o1 is not
             // fall through to generic op
         }
     }

     // fast path for strings
     if (MP_OBJ_IS_STR(o1)) {
         if (MP_OBJ_IS_STR(o2)) {
             // both strings, use special function
             return mp_obj_str_equal(o1, o2);
         } else {
             // a string is never equal to anything else
             return false;
         }
     } else if (MP_OBJ_IS_STR(o2)) {
         // o1 is not a string (else caught above), so the objects are not equal
         return false;
     }

     // generic type, call binary_op(MP_BINARY_OP_EQUAL)
     mp_obj_type_t *type = mp_obj_get_type(o1);
     if (type->binary_op != NULL) {
         mp_obj_t r = type->binary_op(MP_BINARY_OP_EQUAL, o1, o2);
         if (r != MP_OBJ_NULL) {
             return r == mp_const_true ? true : false;
         }
     }

     nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_NotImplementedError,
         "Equality for '%s' and '%s' types not yet implemented", mp_obj_get_type_str(o1), mp_obj_get_type_str(o2)));
     return false;
 }

 mp_int_t mp_obj_get_int(mp_const_obj_t arg) {
     // This function essentially performs implicit type conversion to int
     // Note that Python does NOT provide implicit type conversion from
     // float to int in the core expression language, try some_list[1.0].
     if (arg == mp_const_false) {
         return 0;
     } else if (arg == mp_const_true) {
         return 1;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         return MP_OBJ_SMALL_INT_VALUE(arg);
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         return mp_obj_int_get_checked(arg);
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to int", mp_obj_get_type_str(arg)));
     }
 }

 // returns false if arg is not of integral type
 // returns true and sets *value if it is of integral type
 // can throw OverflowError if arg is of integral type, but doesn't fit in a mp_int_t
 bool mp_obj_get_int_maybe(mp_const_obj_t arg, mp_int_t *value) {
     if (arg == mp_const_false) {
         *value = 0;
     } else if (arg == mp_const_true) {
         *value = 1;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         *value = MP_OBJ_SMALL_INT_VALUE(arg);
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         *value = mp_obj_int_get_checked(arg);
     } else {
         return false;
     }
     return true;
 }

 #if MICROPY_PY_BUILTINS_FLOAT
 mp_float_t mp_obj_get_float(mp_obj_t arg) {
     if (arg == mp_const_false) {
         return 0;
     } else if (arg == mp_const_true) {
         return 1;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         return MP_OBJ_SMALL_INT_VALUE(arg);
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         return mp_obj_int_as_float(arg);
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_float)) {
         return mp_obj_float_get(arg);
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to float", mp_obj_get_type_str(arg)));
     }
 }

 #if MICROPY_PY_BUILTINS_COMPLEX
 void mp_obj_get_complex(mp_obj_t arg, mp_float_t *real, mp_float_t *imag) {
     if (arg == mp_const_false) {
         *real = 0;
         *imag = 0;
     } else if (arg == mp_const_true) {
         *real = 1;
         *imag = 0;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         *real = MP_OBJ_SMALL_INT_VALUE(arg);
         *imag = 0;
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         *real = mp_obj_int_as_float(arg);
         *imag = 0;
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_float)) {
         *real = mp_obj_float_get(arg);
         *imag = 0;
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_complex)) {
         mp_obj_complex_get(arg, real, imag);
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to complex", mp_obj_get_type_str(arg)));
     }
 }
 #endif
 #endif

 void mp_obj_get_array(mp_obj_t o, mp_uint_t *len, mp_obj_t **items) {
     if (MP_OBJ_IS_TYPE(o, &mp_type_tuple)) {
         mp_obj_tuple_get(o, len, items);
     } else if (MP_OBJ_IS_TYPE(o, &mp_type_list)) {
         mp_obj_list_get(o, len, items);
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "object '%s' is not a tuple or list", mp_obj_get_type_str(o)));
     }
 }

 void mp_obj_get_array_fixed_n(mp_obj_t o, mp_uint_t len, mp_obj_t **items) {
     mp_uint_t seq_len;
     mp_obj_get_array(o, &seq_len, items);
     if (seq_len != len) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "requested length %d but object has length %d", len, seq_len));
     }
 }

 // is_slice determines whether the index is a slice index
 mp_uint_t mp_get_index(const mp_obj_type_t *type, mp_uint_t len, mp_obj_t index, bool is_slice) {
     mp_int_t i;
     if (MP_OBJ_IS_SMALL_INT(index)) {
         i = MP_OBJ_SMALL_INT_VALUE(index);
     } else if (!mp_obj_get_int_maybe(index, &i)) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "%s indices must be integers, not %s", qstr_str(type->name), mp_obj_get_type_str(index)));
     }

     if (i < 0) {
         i += len;
     }
     if (is_slice) {
         if (i < 0) {
             i = 0;
         } else if (i > len) {
             i = len;
         }
     } else {
         if (i < 0 || i >= len) {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_IndexError, "%s index out of range", qstr_str(type->name)));
         }
     }
     return i;
 }

 mp_obj_t mp_obj_id(mp_obj_t o_in) {
     mp_int_t id = (mp_int_t)o_in;
     if (!MP_OBJ_IS_OBJ(o_in)) {
         return mp_obj_new_int(id);
     } else if (id >= 0) {
         // Many OSes and CPUs have affinity for putting "user" memories
         // into low half of address space, and "system" into upper half.
         // We're going to take advantage of that and return small int
         // (signed) for such "user" addresses.
         return MP_OBJ_NEW_SMALL_INT(id);
     } else {
         // If that didn't work, well, let's return long int, just as
         // a (big) positve value, so it will never clash with the range
         // of small int returned in previous case.
         return mp_obj_new_int_from_uint((mp_uint_t)id);
     }
 }

 // will raise a TypeError if object has no length
 mp_obj_t mp_obj_len(mp_obj_t o_in) {
     mp_obj_t len = mp_obj_len_maybe(o_in);
     if (len == MP_OBJ_NULL) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "object of type '%s' has no len()", mp_obj_get_type_str(o_in)));
     } else {
         return len;
     }
 }

 // may return MP_OBJ_NULL
 mp_obj_t mp_obj_len_maybe(mp_obj_t o_in) {
     if (
 #if !MICROPY_PY_BUILTINS_STR_UNICODE
         // It's simple - unicode is slow, non-unicode is fast
         MP_OBJ_IS_STR(o_in) ||
 #endif
         MP_OBJ_IS_TYPE(o_in, &mp_type_bytes)) {
         return MP_OBJ_NEW_SMALL_INT(mp_obj_str_get_len(o_in));
     } else {
         mp_obj_type_t *type = mp_obj_get_type(o_in);
         if (type->unary_op != NULL) {
             return type->unary_op(MP_UNARY_OP_LEN, o_in);
         } else {
             return MP_OBJ_NULL;
         }
     }
 }

 mp_obj_t mp_obj_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value) {
     mp_obj_type_t *type = mp_obj_get_type(base);
     if (type->subscr != NULL) {
         mp_obj_t ret = type->subscr(base, index, value);
         if (ret != MP_OBJ_NULL) {
             return ret;
         }
         // TODO: call base classes here?
     }
     if (value == MP_OBJ_NULL) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item deletion", mp_obj_get_type_str(base)));
     } else if (value == MP_OBJ_SENTINEL) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object is not subscriptable", mp_obj_get_type_str(base)));
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item assignment", mp_obj_get_type_str(base)));
     }
 }

 // Return input argument. Useful as .getiter for objects which are
 // their own iterators, etc.
 mp_obj_t mp_identity(mp_obj_t self) {
     return self;
 }
 MP_DEFINE_CONST_FUN_OBJ_1(mp_identity_obj, mp_identity);

 bool mp_get_buffer(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
     mp_obj_type_t *type = mp_obj_get_type(obj);
     if (type->buffer_p.get_buffer == NULL) {
         return false;
     }
     int ret = type->buffer_p.get_buffer(obj, bufinfo, flags);
     if (ret != 0) {
         return false;
     }
     return true;
 }

 void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
     if (!mp_get_buffer(obj, bufinfo, flags)) {
         nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "object with buffer protocol required"));
     }
 }
	/*
	* This file is part of the Micro Python project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2013, 2014 Damien P. George
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#include <stdint.h>
	#include <stdio.h>
	#include <stdarg.h>
	#include <assert.h>

	#include "mpconfig.h"
	#include "nlr.h"
	#include "misc.h"
	#include "qstr.h"
	#include "obj.h"
	#include "objtype.h"
	#include "mpz.h"
	#include "objint.h"
	#include "runtime0.h"
	#include "runtime.h"
	#include "stackctrl.h"

	mp_obj_type_t *mp_obj_get_type(mp_const_obj_t o_in) {
	if (MP_OBJ_IS_SMALL_INT(o_in)) {
	return (mp_obj_t)&mp_type_int;
	} else if (MP_OBJ_IS_QSTR(o_in)) {
	return (mp_obj_t)&mp_type_str;
	} else {
	const mp_obj_base_t *o = o_in;
	return (mp_obj_t)o->type;
	}
	}

	const char *mp_obj_get_type_str(mp_const_obj_t o_in) {
	return qstr_str(mp_obj_get_type(o_in)->name);
	}

	void printf_wrapper(void env, const char fmt, ...) {
	va_list args;
	va_start(args, fmt);
	vprintf(fmt, args);
	va_end(args);
	}

	void mp_obj_print_helper(void (print)(void env, const char fmt, ...), void env, mp_obj_t o_in, mp_print_kind_t kind) {
	// There can be data structures nested too deep, or just recursive
	MP_STACK_CHECK();
	#if !NDEBUG
	if (o_in == NULL) {
	print(env, "(nil)");
	return;
	}
	#endif
	mp_obj_type_t *type = mp_obj_get_type(o_in);
	if (type->print != NULL) {
	type->print(print, env, o_in, kind);
	} else {
	print(env, "<%s>", qstr_str(type->name));
	}
	}

	void mp_obj_print(mp_obj_t o_in, mp_print_kind_t kind) {
	mp_obj_print_helper(printf_wrapper, NULL, o_in, kind);
	}

	// helper function to print an exception with traceback
	void mp_obj_print_exception(mp_obj_t exc) {
	if (mp_obj_is_exception_instance(exc)) {
	mp_uint_t n, *values;
	mp_obj_exception_get_traceback(exc, &n, &values);
	if (n > 0) {
	assert(n % 3 == 0);
	printf("Traceback (most recent call last):\n");
	for (int i = n - 3; i >= 0; i -= 3) {
	#if MICROPY_ENABLE_SOURCE_LINE
	printf(" File \"%s\", line %d", qstr_str(values[i]), (int)values[i + 1]);
	#else
	printf(" File \"%s\"", qstr_str(values[i]));
	#endif
	// the block name can be NULL if it's unknown
	qstr block = values[i + 2];
	if (block == MP_QSTR_NULL) {
	printf("\n");
	} else {
	printf(", in %s\n", qstr_str(block));
	}
	}
	}
	}
	mp_obj_print(exc, PRINT_EXC);
	printf("\n");
	}

	bool mp_obj_is_true(mp_obj_t arg) {
	if (arg == mp_const_false) {
	return 0;
	} else if (arg == mp_const_true) {
	return 1;
	} else if (arg == mp_const_none) {
	return 0;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	if (MP_OBJ_SMALL_INT_VALUE(arg) == 0) {
	return 0;
	} else {
	return 1;
	}
	} else {
	mp_obj_type_t *type = mp_obj_get_type(arg);
	if (type->unary_op != NULL) {
	mp_obj_t result = type->unary_op(MP_UNARY_OP_BOOL, arg);
	if (result != MP_OBJ_NULL) {
	return result == mp_const_true;
	}
	}

	mp_obj_t len = mp_obj_len_maybe(arg);
	if (len != MP_OBJ_NULL) {
	// obj has a length, truth determined if len != 0
	return len != MP_OBJ_NEW_SMALL_INT(0);
	} else {
	// any other obj is true per Python semantics
	return 1;
	}
	}
	}

	bool mp_obj_is_callable(mp_obj_t o_in) {
	mp_call_fun_t call = mp_obj_get_type(o_in)->call;
	if (call != mp_obj_instance_call) {
	return call != NULL;
	}
	return mp_obj_instance_is_callable(o_in);
	}

	mp_int_t mp_obj_hash(mp_obj_t o_in) {
	if (o_in == mp_const_false) {
	return 0; // needs to hash to same as the integer 0, since False==0
	} else if (o_in == mp_const_true) {
	return 1; // needs to hash to same as the integer 1, since True==1
	} else if (MP_OBJ_IS_SMALL_INT(o_in)) {
	return MP_OBJ_SMALL_INT_VALUE(o_in);
	} else if (MP_OBJ_IS_TYPE(o_in, &mp_type_int)) {
	return mp_obj_int_hash(o_in);
	} else if (MP_OBJ_IS_STR(o_in) \|\| MP_OBJ_IS_TYPE(o_in, &mp_type_bytes)) {
	return mp_obj_str_get_hash(o_in);
	} else if (MP_OBJ_IS_TYPE(o_in, &mp_type_NoneType)) {
	return (mp_int_t)o_in;
	} else if (MP_OBJ_IS_FUN(o_in)) {
	return (mp_int_t)o_in;
	} else if (MP_OBJ_IS_TYPE(o_in, &mp_type_tuple)) {
	return mp_obj_tuple_hash(o_in);
	} else if (MP_OBJ_IS_TYPE(o_in, &mp_type_type)) {
	return (mp_int_t)o_in;

	// TODO hash class and instances
	// TODO delegate to __hash__ method if it exists

	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "unhashable type: '%s'", mp_obj_get_type_str(o_in)));
	}
	}

	// this function implements the '==' operator (and so the inverse of '!=')
	// from the python language reference:
	// "The objects need not have the same type. If both are numbers, they are converted
	// to a common type. Otherwise, the == and != operators always consider objects of
	// different types to be unequal."
	// note also that False==0 and True==1 are true expressions
	bool mp_obj_equal(mp_obj_t o1, mp_obj_t o2) {
	if (o1 == o2) {
	return true;
	}
	if (o1 == mp_const_none \|\| o2 == mp_const_none) {
	return false;
	}

	// fast path for small ints
	if (MP_OBJ_IS_SMALL_INT(o1)) {
	if (MP_OBJ_IS_SMALL_INT(o2)) {
	// both SMALL_INT, and not equal if we get here
	return false;
	} else {
	mp_obj_t temp = o2; o2 = o1; o1 = temp;
	// o2 is now the SMALL_INT, o1 is not
	// fall through to generic op
	}
	}

	// fast path for strings
	if (MP_OBJ_IS_STR(o1)) {
	if (MP_OBJ_IS_STR(o2)) {
	// both strings, use special function
	return mp_obj_str_equal(o1, o2);
	} else {
	// a string is never equal to anything else
	return false;
	}
	} else if (MP_OBJ_IS_STR(o2)) {
	// o1 is not a string (else caught above), so the objects are not equal
	return false;
	}

	// generic type, call binary_op(MP_BINARY_OP_EQUAL)
	mp_obj_type_t *type = mp_obj_get_type(o1);
	if (type->binary_op != NULL) {
	mp_obj_t r = type->binary_op(MP_BINARY_OP_EQUAL, o1, o2);
	if (r != MP_OBJ_NULL) {
	return r == mp_const_true ? true : false;
	}
	}

	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_NotImplementedError,
	"Equality for '%s' and '%s' types not yet implemented", mp_obj_get_type_str(o1), mp_obj_get_type_str(o2)));
	return false;
	}

	mp_int_t mp_obj_get_int(mp_const_obj_t arg) {
	// This function essentially performs implicit type conversion to int
	// Note that Python does NOT provide implicit type conversion from
	// float to int in the core expression language, try some_list[1.0].
	if (arg == mp_const_false) {
	return 0;
	} else if (arg == mp_const_true) {
	return 1;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	return MP_OBJ_SMALL_INT_VALUE(arg);
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	return mp_obj_int_get_checked(arg);
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to int", mp_obj_get_type_str(arg)));
	}
	}

	// returns false if arg is not of integral type
	// returns true and sets *value if it is of integral type
	// can throw OverflowError if arg is of integral type, but doesn't fit in a mp_int_t
	bool mp_obj_get_int_maybe(mp_const_obj_t arg, mp_int_t *value) {
	if (arg == mp_const_false) {
	*value = 0;
	} else if (arg == mp_const_true) {
	*value = 1;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	*value = MP_OBJ_SMALL_INT_VALUE(arg);
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	*value = mp_obj_int_get_checked(arg);
	} else {
	return false;
	}
	return true;
	}

	#if MICROPY_PY_BUILTINS_FLOAT
	mp_float_t mp_obj_get_float(mp_obj_t arg) {
	if (arg == mp_const_false) {
	return 0;
	} else if (arg == mp_const_true) {
	return 1;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	return MP_OBJ_SMALL_INT_VALUE(arg);
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	return mp_obj_int_as_float(arg);
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_float)) {
	return mp_obj_float_get(arg);
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to float", mp_obj_get_type_str(arg)));
	}
	}

	#if MICROPY_PY_BUILTINS_COMPLEX
	void mp_obj_get_complex(mp_obj_t arg, mp_float_t real, mp_float_t imag) {
	if (arg == mp_const_false) {
	*real = 0;
	*imag = 0;
	} else if (arg == mp_const_true) {
	*real = 1;
	*imag = 0;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	*real = MP_OBJ_SMALL_INT_VALUE(arg);
	*imag = 0;
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	*real = mp_obj_int_as_float(arg);
	*imag = 0;
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_float)) {
	*real = mp_obj_float_get(arg);
	*imag = 0;
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_complex)) {
	mp_obj_complex_get(arg, real, imag);
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "can't convert %s to complex", mp_obj_get_type_str(arg)));
	}
	}
	#endif
	#endif

	void mp_obj_get_array(mp_obj_t o, mp_uint_t len, mp_obj_t *items) {
	if (MP_OBJ_IS_TYPE(o, &mp_type_tuple)) {
	mp_obj_tuple_get(o, len, items);
	} else if (MP_OBJ_IS_TYPE(o, &mp_type_list)) {
	mp_obj_list_get(o, len, items);
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "object '%s' is not a tuple or list", mp_obj_get_type_str(o)));
	}
	}

	void mp_obj_get_array_fixed_n(mp_obj_t o, mp_uint_t len, mp_obj_t **items) {
	mp_uint_t seq_len;
	mp_obj_get_array(o, &seq_len, items);
	if (seq_len != len) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "requested length %d but object has length %d", len, seq_len));
	}
	}

	// is_slice determines whether the index is a slice index
	mp_uint_t mp_get_index(const mp_obj_type_t *type, mp_uint_t len, mp_obj_t index, bool is_slice) {
	mp_int_t i;
	if (MP_OBJ_IS_SMALL_INT(index)) {
	i = MP_OBJ_SMALL_INT_VALUE(index);
	} else if (!mp_obj_get_int_maybe(index, &i)) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "%s indices must be integers, not %s", qstr_str(type->name), mp_obj_get_type_str(index)));
	}

	if (i < 0) {
	i += len;
	}
	if (is_slice) {
	if (i < 0) {
	i = 0;
	} else if (i > len) {
	i = len;
	}
	} else {
	if (i < 0 \|\| i >= len) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_IndexError, "%s index out of range", qstr_str(type->name)));
	}
	}
	return i;
	}

	mp_obj_t mp_obj_id(mp_obj_t o_in) {
	mp_int_t id = (mp_int_t)o_in;
	if (!MP_OBJ_IS_OBJ(o_in)) {
	return mp_obj_new_int(id);
	} else if (id >= 0) {
	// Many OSes and CPUs have affinity for putting "user" memories
	// into low half of address space, and "system" into upper half.
	// We're going to take advantage of that and return small int
	// (signed) for such "user" addresses.
	return MP_OBJ_NEW_SMALL_INT(id);
	} else {
	// If that didn't work, well, let's return long int, just as
	// a (big) positve value, so it will never clash with the range
	// of small int returned in previous case.
	return mp_obj_new_int_from_uint((mp_uint_t)id);
	}
	}

	// will raise a TypeError if object has no length
	mp_obj_t mp_obj_len(mp_obj_t o_in) {
	mp_obj_t len = mp_obj_len_maybe(o_in);
	if (len == MP_OBJ_NULL) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "object of type '%s' has no len()", mp_obj_get_type_str(o_in)));
	} else {
	return len;
	}
	}

	// may return MP_OBJ_NULL
	mp_obj_t mp_obj_len_maybe(mp_obj_t o_in) {
	if (
	#if !MICROPY_PY_BUILTINS_STR_UNICODE
	// It's simple - unicode is slow, non-unicode is fast
	MP_OBJ_IS_STR(o_in) \|\|
	#endif
	MP_OBJ_IS_TYPE(o_in, &mp_type_bytes)) {
	return MP_OBJ_NEW_SMALL_INT(mp_obj_str_get_len(o_in));
	} else {
	mp_obj_type_t *type = mp_obj_get_type(o_in);
	if (type->unary_op != NULL) {
	return type->unary_op(MP_UNARY_OP_LEN, o_in);
	} else {
	return MP_OBJ_NULL;
	}
	}
	}

	mp_obj_t mp_obj_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value) {
	mp_obj_type_t *type = mp_obj_get_type(base);
	if (type->subscr != NULL) {
	mp_obj_t ret = type->subscr(base, index, value);
	if (ret != MP_OBJ_NULL) {
	return ret;
	}
	// TODO: call base classes here?
	}
	if (value == MP_OBJ_NULL) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item deletion", mp_obj_get_type_str(base)));
	} else if (value == MP_OBJ_SENTINEL) {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object is not subscriptable", mp_obj_get_type_str(base)));
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item assignment", mp_obj_get_type_str(base)));
	}
	}

	// Return input argument. Useful as .getiter for objects which are
	// their own iterators, etc.
	mp_obj_t mp_identity(mp_obj_t self) {
	return self;
	}
	MP_DEFINE_CONST_FUN_OBJ_1(mp_identity_obj, mp_identity);

	bool mp_get_buffer(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
	mp_obj_type_t *type = mp_obj_get_type(obj);
	if (type->buffer_p.get_buffer == NULL) {
	return false;
	}
	int ret = type->buffer_p.get_buffer(obj, bufinfo, flags);
	if (ret != 0) {
	return false;
	}
	return true;
	}

	void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
	if (!mp_get_buffer(obj, bufinfo, flags)) {
	nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "object with buffer protocol required"));
	}
	}