document reflect.
R=rsc
DELTA=201 (90 added, 0 deleted, 111 changed)
OCL=25904
CL=25966
diff --git a/src/lib/reflect/value.go b/src/lib/reflect/value.go
index 9056d74..f4e6340 100644
--- a/src/lib/reflect/value.go
+++ b/src/lib/reflect/value.go
@@ -12,16 +12,25 @@
"unsafe";
)
+// Addr is shorthand for unsafe.Pointer and is used to represent the address of Values.
type Addr unsafe.Pointer
func equalType(a, b Type) bool {
return a.String() == b.String()
}
+// Value is the generic interface to reflection values. Once its Kind is known,
+// such as BoolKind, the Value can be narrowed to the appropriate, more
+// specific interface, such as BoolValue. Such narrowed values still implement
+// the Value interface.
type Value interface {
+ // The kind of thing described: ArrayKind, BoolKind, etc.
Kind() int;
+ // The reflection Type of the value.
Type() Type;
+ // The address of the value.
Addr() Addr;
+ // The value itself is the dynamic value of an empty interface.
Interface() interface {};
}
@@ -65,6 +74,8 @@
// -- Missing
+// MissingValue represents a value whose type is not known. It usually
+// indicates an error.
type MissingValue interface {
Value;
}
@@ -79,10 +90,11 @@
// -- Int
+// IntValue represents an int value.
type IntValue interface {
Value;
- Get() int;
- Set(int);
+ Get() int; // Get the underlying int.
+ Set(int); // Set the underlying int.
}
type intValueStruct struct {
@@ -103,10 +115,11 @@
// -- Int8
+// Int8Value represents an int8 value.
type Int8Value interface {
Value;
- Get() int8;
- Set(int8);
+ Get() int8; // Get the underlying int8.
+ Set(int8); // Set the underlying int8.
}
type int8ValueStruct struct {
@@ -127,10 +140,11 @@
// -- Int16
+// Int16Value represents an int16 value.
type Int16Value interface {
Value;
- Get() int16;
- Set(int16);
+ Get() int16; // Get the underlying int16.
+ Set(int16); // Set the underlying int16.
}
type int16ValueStruct struct {
@@ -151,10 +165,11 @@
// -- Int32
+// Int32Value represents an int32 value.
type Int32Value interface {
Value;
- Get() int32;
- Set(int32);
+ Get() int32; // Get the underlying int32.
+ Set(int32); // Set the underlying int32.
}
type int32ValueStruct struct {
@@ -175,10 +190,11 @@
// -- Int64
+// Int64Value represents an int64 value.
type Int64Value interface {
Value;
- Get() int64;
- Set(int64);
+ Get() int64; // Get the underlying int64.
+ Set(int64); // Set the underlying int64.
}
type int64ValueStruct struct {
@@ -199,10 +215,11 @@
// -- Uint
+// UintValue represents a uint value.
type UintValue interface {
Value;
- Get() uint;
- Set(uint);
+ Get() uint; // Get the underlying uint.
+ Set(uint); // Set the underlying uint.
}
type uintValueStruct struct {
@@ -223,10 +240,11 @@
// -- Uint8
+// Uint8Value represents a uint8 value.
type Uint8Value interface {
Value;
- Get() uint8;
- Set(uint8);
+ Get() uint8; // Get the underlying uint8.
+ Set(uint8); // Set the underlying uint8.
}
type uint8ValueStruct struct {
@@ -247,10 +265,11 @@
// -- Uint16
+// Uint16Value represents a uint16 value.
type Uint16Value interface {
Value;
- Get() uint16;
- Set(uint16);
+ Get() uint16; // Get the underlying uint16.
+ Set(uint16); // Set the underlying uint16.
}
type uint16ValueStruct struct {
@@ -271,10 +290,11 @@
// -- Uint32
+// Uint32Value represents a uint32 value.
type Uint32Value interface {
Value;
- Get() uint32;
- Set(uint32);
+ Get() uint32; // Get the underlying uint32.
+ Set(uint32); // Set the underlying uint32.
}
type uint32ValueStruct struct {
@@ -295,10 +315,11 @@
// -- Uint64
+// Uint64Value represents a uint64 value.
type Uint64Value interface {
Value;
- Get() uint64;
- Set(uint64);
+ Get() uint64; // Get the underlying uint64.
+ Set(uint64); // Set the underlying uint64.
}
type uint64ValueStruct struct {
@@ -319,10 +340,11 @@
// -- Uintptr
+// UintptrValue represents a uintptr value.
type UintptrValue interface {
Value;
- Get() uintptr;
- Set(uintptr);
+ Get() uintptr; // Get the underlying uintptr.
+ Set(uintptr); // Set the underlying uintptr.
}
type uintptrValueStruct struct {
@@ -343,10 +365,11 @@
// -- Float
+// FloatValue represents a float value.
type FloatValue interface {
Value;
- Get() float;
- Set(float);
+ Get() float; // Get the underlying float.
+ Set(float); // Get the underlying float.
}
type floatValueStruct struct {
@@ -367,10 +390,11 @@
// -- Float32
+// Float32Value represents a float32 value.
type Float32Value interface {
Value;
- Get() float32;
- Set(float32);
+ Get() float32; // Get the underlying float32.
+ Set(float32); // Get the underlying float32.
}
type float32ValueStruct struct {
@@ -391,10 +415,11 @@
// -- Float64
+// Float64Value represents a float64 value.
type Float64Value interface {
Value;
- Get() float64;
- Set(float64);
+ Get() float64; // Get the underlying float64.
+ Set(float64); // Get the underlying float64.
}
type float64ValueStruct struct {
@@ -415,10 +440,11 @@
// -- Float80
+// Float80Value represents a float80 value.
type Float80Value interface {
Value;
- Get() float80;
- Set(float80);
+ Get() float80; // Get the underlying float80.
+ Set(float80); // Get the underlying float80.
}
type float80ValueStruct struct {
@@ -442,10 +468,11 @@
// -- String
+// StringValue represents a string value.
type StringValue interface {
Value;
- Get() string;
- Set(string);
+ Get() string; // Get the underlying string value.
+ Set(string); // Set the underlying string value.
}
type stringValueStruct struct {
@@ -466,10 +493,11 @@
// -- Bool
+// BoolValue represents a bool value.
type BoolValue interface {
Value;
- Get() bool;
- Set(bool);
+ Get() bool; // Get the underlying bool value.
+ Set(bool); // Set the underlying bool value.
}
type boolValueStruct struct {
@@ -490,11 +518,12 @@
// -- Pointer
+// PtrValue represents a pointer value.
type PtrValue interface {
Value;
- Sub() Value;
- Get() Addr;
- SetSub(Value);
+ Sub() Value; // The Value pointed to.
+ Get() Addr; // Get the address stored in the pointer.
+ SetSub(Value); // Set the the pointed-to Value.
}
type ptrValueStruct struct {
@@ -526,15 +555,16 @@
// -- Array
// Slices and arrays are represented by the same interface.
+// ArrayValue represents an array or slice value.
type ArrayValue interface {
Value;
- IsSlice() bool;
- Len() int;
- Cap() int;
- Elem(i int) Value;
- SetLen(len int);
- Set(src ArrayValue);
- CopyFrom(src ArrayValue, n int)
+ IsSlice() bool; // Is this a slice (true) or array (false)?
+ Len() int; // The length of the array/slice.
+ Cap() int; // The capacity of the array/slice (==Len() for arrays).
+ Elem(i int) Value; // The Value of the i'th element.
+ SetLen(len int); // Set the length; slice only.
+ Set(src ArrayValue); // Set the underlying Value; slice only for src and dest both.
+ CopyFrom(src ArrayValue, n int) // Copy the elements from src; lengths must match.
}
func copyArray(dst ArrayValue, src ArrayValue, n int);
@@ -581,7 +611,7 @@
func (v *sliceValueStruct) Set(src ArrayValue) {
if !src.IsSlice() {
- panic("can't set from fixed array");
+ panic("can't set slice from array");
}
s := src.(*sliceValueStruct);
if !equalType(v.typ, s.typ) {
@@ -619,10 +649,11 @@
}
func (v *arrayValueStruct) SetLen(len int) {
+ panicln("can't set len of array");
}
func (v *arrayValueStruct) Set(src ArrayValue) {
- panicln("can't set fixed array");
+ panicln("can't set array");
}
func (v *arrayValueStruct) Elem(i int) Value {
@@ -659,10 +690,12 @@
// -- Map TODO: finish and test
+// MapValue represents a map value.
+// Its implementation is incomplete.
type MapValue interface {
Value;
- Len() int;
- Elem(key Value) Value;
+ Len() int; // The number of elements; currently always returns 0.
+ Elem(key Value) Value; // The value indexed by key; unimplemented.
}
type mapValueStruct struct {
@@ -684,6 +717,8 @@
// -- Chan
+// ChanValue represents a chan value.
+// Its implementation is incomplete.
type ChanValue interface {
Value;
}
@@ -698,10 +733,11 @@
// -- Struct
+// StructValue represents a struct value.
type StructValue interface {
Value;
- Len() int;
- Field(i int) Value;
+ Len() int; // The number of fields.
+ Field(i int) Value; // The Value of field i.
}
type structValueStruct struct {
@@ -732,9 +768,10 @@
// -- Interface
+// InterfaceValue represents an interface value.
type InterfaceValue interface {
Value;
- Get() interface {};
+ Get() interface {}; // Get the underlying interface{} value.
}
type interfaceValueStruct struct {
@@ -751,6 +788,9 @@
// -- Func
+
+// FuncValue represents a func value.
+// Its implementation is incomplete.
type FuncValue interface {
Value;
}
@@ -801,6 +841,7 @@
return c(typ, addr);
}
+// NewInitValue creates a new, zero-initialized Value for the specified Type.
func NewInitValue(typ Type) Value {
// Some values cannot be made this way.
switch typ.Kind() {
@@ -819,6 +860,8 @@
return newValueAddr(typ, Addr(&data[0]));
}
+// NewSliceValue creates a new, zero-initialized slice value (ArrayValue) for the specified
+// slice type (ArrayType), length, and capacity.
func NewSliceValue(typ ArrayType, len, cap int) ArrayValue {
if !typ.IsSlice() {
return nil
@@ -869,7 +912,7 @@
}
}
-
+// NewValue creates a new Value from the interface{} object provided.
func NewValue(e interface {}) Value {
value, typestring, indir := sys.Reflect(e);
typ, ok := typecache[typestring];
