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

 /*
  * This file is part of the MicroPython 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 "py/obj.h"
 #include "py/objtype.h"
 #include "py/objint.h"
 #include "py/objstr.h"
 #include "py/runtime.h"
 #include "py/stackctrl.h"
 #include "py/stream.h" // for mp_obj_print

 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_type_t*)&mp_type_int;
     } else if (MP_OBJ_IS_QSTR(o_in)) {
         return (mp_obj_type_t*)&mp_type_str;
     #if MICROPY_PY_BUILTINS_FLOAT
     } else if (mp_obj_is_float(o_in)) {
         return (mp_obj_type_t*)&mp_type_float;
     #endif
     } else {
         const mp_obj_base_t *o = MP_OBJ_TO_PTR(o_in);
         return (mp_obj_type_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 mp_obj_print_helper(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
     // There can be data structures nested too deep, or just recursive
     MP_STACK_CHECK();
 #ifndef NDEBUG
     if (o_in == MP_OBJ_NULL) {
         mp_print_str(print, "(nil)");
         return;
     }
 #endif
     mp_obj_type_t *type = mp_obj_get_type(o_in);
     if (type->print != NULL) {
         type->print((mp_print_t*)print, o_in, kind);
     } else {
         mp_printf(print, "<%q>", type->name);
     }
 }

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

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

 // This function implements the '==' operator (and so the inverse of '!=').
 //
 // From the Python language reference:
 // (https://docs.python.org/3/reference/expressions.html#not-in)
 // "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."
 //
 // This means that False==0 and True==1 are true expressions.
 //
 // Furthermore, from the v3.4.2 code for object.c: "Practical amendments: If rich
 // comparison returns NotImplemented, == and != are decided by comparing the object
 // pointer."
 bool mp_obj_equal(mp_obj_t o1, mp_obj_t o2) {
     // Float (and complex) NaN is never equal to anything, not even itself,
     // so we must have a special check here to cover those cases.
     if (o1 == o2
         #if MICROPY_PY_BUILTINS_FLOAT
         && !mp_obj_is_float(o1)
         #endif
         #if MICROPY_PY_BUILTINS_COMPLEX
         && !MP_OBJ_IS_TYPE(o1, &mp_type_complex)
         #endif
         ) {
         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
             goto str_cmp_err;
         }
     } else if (MP_OBJ_IS_STR(o2)) {
         // o1 is not a string (else caught above), so the objects are not equal
     str_cmp_err:
         #if MICROPY_PY_STR_BYTES_CMP_WARN
         if (MP_OBJ_IS_TYPE(o1, &mp_type_bytes) || MP_OBJ_IS_TYPE(o2, &mp_type_bytes)) {
             mp_warning("Comparison between bytes and str");
         }
         #endif
         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;
         }
     }

     // equality not implemented, and objects are not the same object, so
     // they are defined as not equal
     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 {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("can't convert to int");
         } else {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
                 "can't convert %s to int", mp_obj_get_type_str(arg)));
         }
     }
 }

 mp_int_t mp_obj_get_int_truncated(mp_const_obj_t arg) {
     if (MP_OBJ_IS_INT(arg)) {
         return mp_obj_int_get_truncated(arg);
     } else {
         return mp_obj_get_int(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
 bool mp_obj_get_float_maybe(mp_obj_t arg, mp_float_t *value) {
     mp_float_t val;

     if (arg == mp_const_false) {
         val = 0;
     } else if (arg == mp_const_true) {
         val = 1;
     } else if (MP_OBJ_IS_SMALL_INT(arg)) {
         val = MP_OBJ_SMALL_INT_VALUE(arg);
     #if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         val = mp_obj_int_as_float_impl(arg);
     #endif
     } else if (mp_obj_is_float(arg)) {
         val = mp_obj_float_get(arg);
     } else {
         return false;
     }

     *value = val;
     return true;
 }

 mp_float_t mp_obj_get_float(mp_obj_t arg) {
     mp_float_t val;

     if (!mp_obj_get_float_maybe(arg, &val)) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("can't convert to float");
         } else {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
                 "can't convert %s to float", mp_obj_get_type_str(arg)));
         }
     }

     return val;
 }

 #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;
     #if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
     } else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
         *real = mp_obj_int_as_float_impl(arg);
         *imag = 0;
     #endif
     } else if (mp_obj_is_float(arg)) {
         *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 {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("can't convert to complex");
         } 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

 // note: returned value in *items may point to the interior of a GC block
 void mp_obj_get_array(mp_obj_t o, size_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 {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("expected tuple/list");
         } 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)));
         }
     }
 }

 // note: returned value in *items may point to the interior of a GC block
 void mp_obj_get_array_fixed_n(mp_obj_t o, size_t len, mp_obj_t **items) {
     size_t seq_len;
     mp_obj_get_array(o, &seq_len, items);
     if (seq_len != len) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_ValueError("tuple/list has wrong length");
         } else {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
                 "requested length %d but object has length %d", (int)len, (int)seq_len));
         }
     }
 }

 // is_slice determines whether the index is a slice index
 size_t mp_get_index(const mp_obj_type_t *type, size_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)) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("indices must be integers");
         } else {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
                 "%q indices must be integers, not %s",
                 type->name, mp_obj_get_type_str(index)));
         }
     }

     if (i < 0) {
         i += len;
     }
     if (is_slice) {
         if (i < 0) {
             i = 0;
         } else if ((mp_uint_t)i > len) {
             i = len;
         }
     } else {
         if (i < 0 || (mp_uint_t)i >= len) {
             if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
                 mp_raise_msg(&mp_type_IndexError, "index out of range");
             } else {
                 nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_IndexError,
                     "%q index out of range", type->name));
             }
         }
     }

     // By this point 0 <= i <= len and so fits in a size_t
     return (size_t)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) positive 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) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("object has no len");
         } else {
             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)) {
         GET_STR_LEN(o_in, l);
         return MP_OBJ_NEW_SMALL_INT(l);
     } 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) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("object does not support item deletion");
         } else {
             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) {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("object is not subscriptable");
         } else {
             nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
                 "'%s' object is not subscriptable", mp_obj_get_type_str(base)));
         }
     } else {
         if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
             mp_raise_TypeError("object does not support item assignment");
         } 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);

 mp_obj_t mp_identity_getiter(mp_obj_t self, mp_obj_iter_buf_t *iter_buf) {
     (void)iter_buf;
     return self;
 }

 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)) {
         mp_raise_TypeError("object with buffer protocol required");
     }
 }

 mp_obj_t mp_generic_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     switch (op) {
         case MP_UNARY_OP_HASH: return MP_OBJ_NEW_SMALL_INT((mp_uint_t)o_in);
         default: return MP_OBJ_NULL; // op not supported
     }
 }
	/*
	* This file is part of the MicroPython 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 "py/obj.h"
	#include "py/objtype.h"
	#include "py/objint.h"
	#include "py/objstr.h"
	#include "py/runtime.h"
	#include "py/stackctrl.h"
	#include "py/stream.h" // for mp_obj_print

	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_type_t*)&mp_type_int;
	} else if (MP_OBJ_IS_QSTR(o_in)) {
	return (mp_obj_type_t*)&mp_type_str;
	#if MICROPY_PY_BUILTINS_FLOAT
	} else if (mp_obj_is_float(o_in)) {
	return (mp_obj_type_t*)&mp_type_float;
	#endif
	} else {
	const mp_obj_base_t *o = MP_OBJ_TO_PTR(o_in);
	return (mp_obj_type_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 mp_obj_print_helper(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
	// There can be data structures nested too deep, or just recursive
	MP_STACK_CHECK();
	#ifndef NDEBUG
	if (o_in == MP_OBJ_NULL) {
	mp_print_str(print, "(nil)");
	return;
	}
	#endif
	mp_obj_type_t *type = mp_obj_get_type(o_in);
	if (type->print != NULL) {
	type->print((mp_print_t*)print, o_in, kind);
	} else {
	mp_printf(print, "<%q>", type->name);
	}
	}

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

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

	// This function implements the '==' operator (and so the inverse of '!=').
	//
	// From the Python language reference:
	// (https://docs.python.org/3/reference/expressions.html#not-in)
	// "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."
	//
	// This means that False==0 and True==1 are true expressions.
	//
	// Furthermore, from the v3.4.2 code for object.c: "Practical amendments: If rich
	// comparison returns NotImplemented, == and != are decided by comparing the object
	// pointer."
	bool mp_obj_equal(mp_obj_t o1, mp_obj_t o2) {
	// Float (and complex) NaN is never equal to anything, not even itself,
	// so we must have a special check here to cover those cases.
	if (o1 == o2
	#if MICROPY_PY_BUILTINS_FLOAT
	&& !mp_obj_is_float(o1)
	#endif
	#if MICROPY_PY_BUILTINS_COMPLEX
	&& !MP_OBJ_IS_TYPE(o1, &mp_type_complex)
	#endif
	) {
	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
	goto str_cmp_err;
	}
	} else if (MP_OBJ_IS_STR(o2)) {
	// o1 is not a string (else caught above), so the objects are not equal
	str_cmp_err:
	#if MICROPY_PY_STR_BYTES_CMP_WARN
	if (MP_OBJ_IS_TYPE(o1, &mp_type_bytes) \|\| MP_OBJ_IS_TYPE(o2, &mp_type_bytes)) {
	mp_warning("Comparison between bytes and str");
	}
	#endif
	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;
	}
	}

	// equality not implemented, and objects are not the same object, so
	// they are defined as not equal
	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 {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("can't convert to int");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
	"can't convert %s to int", mp_obj_get_type_str(arg)));
	}
	}
	}

	mp_int_t mp_obj_get_int_truncated(mp_const_obj_t arg) {
	if (MP_OBJ_IS_INT(arg)) {
	return mp_obj_int_get_truncated(arg);
	} else {
	return mp_obj_get_int(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
	bool mp_obj_get_float_maybe(mp_obj_t arg, mp_float_t *value) {
	mp_float_t val;

	if (arg == mp_const_false) {
	val = 0;
	} else if (arg == mp_const_true) {
	val = 1;
	} else if (MP_OBJ_IS_SMALL_INT(arg)) {
	val = MP_OBJ_SMALL_INT_VALUE(arg);
	#if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	val = mp_obj_int_as_float_impl(arg);
	#endif
	} else if (mp_obj_is_float(arg)) {
	val = mp_obj_float_get(arg);
	} else {
	return false;
	}

	*value = val;
	return true;
	}

	mp_float_t mp_obj_get_float(mp_obj_t arg) {
	mp_float_t val;

	if (!mp_obj_get_float_maybe(arg, &val)) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("can't convert to float");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
	"can't convert %s to float", mp_obj_get_type_str(arg)));
	}
	}

	return val;
	}

	#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;
	#if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
	} else if (MP_OBJ_IS_TYPE(arg, &mp_type_int)) {
	*real = mp_obj_int_as_float_impl(arg);
	*imag = 0;
	#endif
	} else if (mp_obj_is_float(arg)) {
	*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 {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("can't convert to complex");
	} 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

	// note: returned value in *items may point to the interior of a GC block
	void mp_obj_get_array(mp_obj_t o, size_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 {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("expected tuple/list");
	} 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)));
	}
	}
	}

	// note: returned value in *items may point to the interior of a GC block
	void mp_obj_get_array_fixed_n(mp_obj_t o, size_t len, mp_obj_t **items) {
	size_t seq_len;
	mp_obj_get_array(o, &seq_len, items);
	if (seq_len != len) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_ValueError("tuple/list has wrong length");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
	"requested length %d but object has length %d", (int)len, (int)seq_len));
	}
	}
	}

	// is_slice determines whether the index is a slice index
	size_t mp_get_index(const mp_obj_type_t *type, size_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)) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("indices must be integers");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
	"%q indices must be integers, not %s",
	type->name, mp_obj_get_type_str(index)));
	}
	}

	if (i < 0) {
	i += len;
	}
	if (is_slice) {
	if (i < 0) {
	i = 0;
	} else if ((mp_uint_t)i > len) {
	i = len;
	}
	} else {
	if (i < 0 \|\| (mp_uint_t)i >= len) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_msg(&mp_type_IndexError, "index out of range");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_IndexError,
	"%q index out of range", type->name));
	}
	}
	}

	// By this point 0 <= i <= len and so fits in a size_t
	return (size_t)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) positive 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) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("object has no len");
	} else {
	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)) {
	GET_STR_LEN(o_in, l);
	return MP_OBJ_NEW_SMALL_INT(l);
	} 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) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("object does not support item deletion");
	} else {
	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) {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("object is not subscriptable");
	} else {
	nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError,
	"'%s' object is not subscriptable", mp_obj_get_type_str(base)));
	}
	} else {
	if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
	mp_raise_TypeError("object does not support item assignment");
	} 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);

	mp_obj_t mp_identity_getiter(mp_obj_t self, mp_obj_iter_buf_t *iter_buf) {
	(void)iter_buf;
	return self;
	}

	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)) {
	mp_raise_TypeError("object with buffer protocol required");
	}
	}

	mp_obj_t mp_generic_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
	switch (op) {
	case MP_UNARY_OP_HASH: return MP_OBJ_NEW_SMALL_INT((mp_uint_t)o_in);
	default: return MP_OBJ_NULL; // op not supported
	}
	}