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typeof
The typeof
language construction provides information about
some Poke type. It has the form:
typeof (entity)
where entity is either a value or a type specifier. It returns
a Pk_Type
value describing either the specified type, or the
type of the specified value.
The Pk_Type
struct provides the following fields for all kind
of types:
uint<32> code
This is a numerical code that identifies the kind of the described type.
Valid codes are PK_TYPE_UNKNOWN
, PK_TYPE_INTEGRAL
,
PK_TYPE_OFFSET
, PK_TYPE_STRING
, PK_TYPE_ARRAY
,
PK_TYPE_STRUCT
, PK_TYPE_FUNCTION
and PK_TYPE_ANY
.
string name
If the described type is named, then this field contains the name. Otherwise it is the empty string.
(poke) type myint = int (poke) typeof (1 as myint) Pk_Type { code=1, name="myint", [...] }
int<32> complete_p
If the size of the described type can be determined at compile time, then this field is 1, 0 otherwise.
The following fields are provided in Pk_Type
only for integral,
offset and integral struct types:
int<32> signed_p
If the described type is signed, this field is 1, 0 otherwise.
uint<64> size
The number of bits of values of the described integral type, or the number of bits of the integral value of the described integral struct type, or the number of bits of the magnitude of the described offset type.
This would be 23UL for an int<23>
type, and 32UL for an
offset<int<32>,1>
type.
The following fields are provided in Pk_Type
only for
offset types:
_unit
The unit of the described offset type, in bit units. This would be
8UL for an offset<int<32>,B>
type, for example.
The following fields are provided in Pk_Type
only for array
types:
int<32> bounded_p
This field is 1 if the described array type is bounded by either number of elements or by size, 0 otherwise.
The following fields are provided in Pk_Type
only for struct
types:
int<32> union_p
This field is 1 if the described struct type is an union, 0 otherwise.
int<32> pinned_p
This field is 1 if the described struct type is pinned, 0 otherwise.
int<32> integral_p
This field is 1 if the described struct type is integral, 0 otherwise.
int<32> nfields
Number of fields defined in the described struct type. This count includes optional fields and computed fields.
int<32> nmethods
Number of methods defined in the described struct type.
string[] fnames
Array of nfields
strings, with the names of the fields defined
in the described struct type. Anonymous fields feature empty strings.
int<32>[] fcomputed
Array of nfields
integers, which are 1 for fields that are
computed, 0 for fields that are not computed.
string[] ftypes
Array of nfields
strings, with the type specifiers of the types
of the fields defined in the described struct type.
string[] mnames
Array of nmethods
strings, with the names of the methods
defined in the described struct type.
string[] mtypes
Array of nmethods
strings, with the type specifiers of the
types of the methods defined in the described struct type.
(any)any deintegrator
Closure that, when passed an integral value of the same signedness and width than the described integral struct, returns the struct value corresponding to that value.
(poke) type Foo = struct int<32> { int<16> a; uint<16> b; } (poke) typeof (Foo).deintegrator (0x0eadbeef) Foo { a=0x0eadH, b=0xbeefUH }
The following fields are provided in Pk_Type
only for struct
and array types:
(int<32>,int<32>,uint<64>)any mapper
Closure that, when passed an integer predicate denoting whether to do a strict mapping, an IO space identifier, a bit-offset in the given IO space, map a value of the described type.
(any)void writer
Closure that, when passed a mapped value of the described type, writes the contents of the value to the corresponding IO space.
(any)any integrator
Closure that, when passed a value of the described type (an array type or an integral struct type) returns the integral value corresponding to the contents of the value.
(poke) type Foo = struct int<32> { int<16> a; uint<16> b; } (poke) typeof (Foo).integrator (Foo { a = 0xab, b = 0xcd }) 0x00ab00cd
(any,any)int<32> comparator
Closure that, when passed two values of the described type, returns 1 if the values are equal,0 otherwise.
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