Standard Types

The following are the Scheme_Type values for the standard types:

• scheme_char_type -- SCHEME_CHAR_VAL extracts the character; test for this type with SCHEME_CHARP
• scheme_integer_type -- fixnum integers, which are identified via the tag bit rather than following a pointer to this Scheme_Type value; SCHEME_INT_VAL extracts the integer; test for this type with SCHEME_INTP
• scheme_double_type -- flonum inexact numbers; SCHEME_FLOAT_VAL or SCHEME_DBL_VAL extracts the floating-point value; test for this type with SCHEME_DBLP
• scheme_float_type -- single-precision flonum inexact numbers, when specifically enabled when compiling MzScheme; SCHEME_FLOAT_VAL or SCHEME_FLT_VAL extracts the floating-point value; test for this type with SCHEME_FLTP
• scheme_bignum_type -- test for this type with SCHEME_BIGNUMP
• scheme_rational_type -- test for this type with SCHEME_RATIONALP
• scheme_complex_type -- test for this type or scheme_complex_izi_type with SCHEME_COMPLEXP
• scheme_complex_izi_type -- complex number with an inexact zero imaginary part (so it counts as a real number); test for this type specifically with SCHEME_COMPLEX_IZIP
• scheme_string_type -- SCHEME_STR_VAL extracts the string (which is always null-terminated, but may also contain embedded nulls; the Scheme string is modified if this string is modified) and SCHEME_STRLEN_VAL extracts the string length (not counting the null terminator); test for this type with SCHEME_STRINGP
• scheme_symbol_type -- SCHEME_SYM_VAL extracts the string (do not modify this string); test for this type with SCHEME_SYMBOLP
• scheme_box_type -- SCHEME_BOX_VAL extracts/sets the boxed value; test for this type with SCHEME_BOXP
• scheme_pair_type -- SCHEME_CAR extracts/sets the car and SCHEME_CDR extracts/sets the cdr; test for this type with SCHEME_PAIRP
• scheme_vector_type -- SCHEME_VEC_SIZE extracts the length and SCHEME_VEC_ELS extracts the array or Scheme values (the Scheme vector is modified when this array is modified); test for this type with SCHEME_VECTORP
• scheme_type_symbol_type -- SCHEME_TSYM_VAL extracts the symbol; test for this type with SCHEME_TSYMBOLP
• scheme_object_type -- SCHEME_OBJ_CLASS extracts the class, SCHEME_OBJ_DATA extracts/sets the user pointer, and SCHEME_OBJ_FLAG extracts/sets the flag; test for this type with SCHEME_OBJP
• scheme_class_type -- test for this type with SCHEME_CLASSP
• scheme_interface_type -- test for this type with SCHEME_INTERFACEP
• scheme_structure_type -- structure instances; test for this type with SCHEME_STRUCTP
• scheme_struct_type_type -- structure types; test for this type with SCHEME_STRUCT_TYPEP
• scheme_unit_type -- test for this type with SCHEME_UNITP
• scheme_input_port_type -- SCHEME_INPORT_VAL extracts/sets the user data pointer; test for this type with SCHEME_INPORTP
• scheme_output_port_type -- SCHEME_OUTPORT_VAL extracts/sets the user data pointer; test for this type with SCHEME_OUTPORTP
• scheme_promise_type -- test for this type with SCHEME_PROMP
• scheme_process_type -- thread descriptors; test for this type with SCHEME_PROCESSP
• scheme_sema_type -- semaphores; test for this type with SCHEME_SEMAP
• scheme_hash_table_type -- test for this type with SCHEME_HASHTP
• scheme_weak_box_type -- test for this type with SCHEME_WEAKP; SCHEME_WEAK_PTR extracts the contained object, or NULL after the content is collected; do not set the content of a weak box
• scheme_generic_data_type -- data analogous to a generic procedure created with make-generic; test for this type with SCHEME_GENDATAP
• scheme_namespace_type -- namespaces; test for this type with SCHEME_NAMESPACEP
• scheme_config_type -- parameterizations; test for this type with SCHEME_CONFIGP

The following are the procedure types:

• scheme_prim_type -- a primitive procedure
• scheme_closed_prim_type -- a primitive procedure with a data pointer
• scheme_compiled_closure_type -- a Scheme procedure
• scheme_cont_type -- a continuation
• scheme_escaping_cont_type -- an escape continuation
• scheme_case_closure_type -- a case-lambda procedure

The predicate SCHEME_PROCP returns 1 for all procedure types and 0 for anything else.

The following are additional number predicates:

• SCHEME_NUMBERP -- all numerical types
• SCHEME_REALP -- all non-complex numerical types, plus scheme_complex_izi_type
• SCHEME_EXACT_INTEGERP -- fixnums and bignums
• SCHEME_EXACT_REALP -- fixnums, bignums, and rationals
• SCHEME_FLOATP -- both single-precision (when enabled) and double-precision flonums