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Diffstat (limited to 'src/pkg/reflect/makefunc.go')
| -rw-r--r-- | src/pkg/reflect/makefunc.go | 120 |
1 files changed, 0 insertions, 120 deletions
diff --git a/src/pkg/reflect/makefunc.go b/src/pkg/reflect/makefunc.go deleted file mode 100644 index 0e61fdea7..000000000 --- a/src/pkg/reflect/makefunc.go +++ /dev/null @@ -1,120 +0,0 @@ -// Copyright 2012 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// MakeFunc implementation. - -package reflect - -import ( - "unsafe" -) - -// makeFuncImpl is the closure value implementing the function -// returned by MakeFunc. -type makeFuncImpl struct { - code uintptr - typ *funcType - fn func([]Value) []Value -} - -// MakeFunc returns a new function of the given Type -// that wraps the function fn. When called, that new function -// does the following: -// -// - converts its arguments to a slice of Values. -// - runs results := fn(args). -// - returns the results as a slice of Values, one per formal result. -// -// The implementation fn can assume that the argument Value slice -// has the number and type of arguments given by typ. -// If typ describes a variadic function, the final Value is itself -// a slice representing the variadic arguments, as in the -// body of a variadic function. The result Value slice returned by fn -// must have the number and type of results given by typ. -// -// The Value.Call method allows the caller to invoke a typed function -// in terms of Values; in contrast, MakeFunc allows the caller to implement -// a typed function in terms of Values. -// -// The Examples section of the documentation includes an illustration -// of how to use MakeFunc to build a swap function for different types. -// -func MakeFunc(typ Type, fn func(args []Value) (results []Value)) Value { - if typ.Kind() != Func { - panic("reflect: call of MakeFunc with non-Func type") - } - - t := typ.common() - ftyp := (*funcType)(unsafe.Pointer(t)) - - // Indirect Go func value (dummy) to obtain - // actual code address. (A Go func value is a pointer - // to a C function pointer. http://golang.org/s/go11func.) - dummy := makeFuncStub - code := **(**uintptr)(unsafe.Pointer(&dummy)) - - impl := &makeFuncImpl{code: code, typ: ftyp, fn: fn} - - return Value{t, unsafe.Pointer(impl), 0, flag(Func) << flagKindShift} -} - -// makeFuncStub is an assembly function that is the code half of -// the function returned from MakeFunc. It expects a *callReflectFunc -// as its context register, and its job is to invoke callReflect(ctxt, frame) -// where ctxt is the context register and frame is a pointer to the first -// word in the passed-in argument frame. -func makeFuncStub() - -type methodValue struct { - fn uintptr - method int - rcvr Value -} - -// makeMethodValue converts v from the rcvr+method index representation -// of a method value to an actual method func value, which is -// basically the receiver value with a special bit set, into a true -// func value - a value holding an actual func. The output is -// semantically equivalent to the input as far as the user of package -// reflect can tell, but the true func representation can be handled -// by code like Convert and Interface and Assign. -func makeMethodValue(op string, v Value) Value { - if v.flag&flagMethod == 0 { - panic("reflect: internal error: invalid use of makeMethodValue") - } - - // Ignoring the flagMethod bit, v describes the receiver, not the method type. - fl := v.flag & (flagRO | flagAddr | flagIndir) - fl |= flag(v.typ.Kind()) << flagKindShift - rcvr := Value{v.typ, v.ptr, v.scalar, fl} - - // v.Type returns the actual type of the method value. - funcType := v.Type().(*rtype) - - // Indirect Go func value (dummy) to obtain - // actual code address. (A Go func value is a pointer - // to a C function pointer. http://golang.org/s/go11func.) - dummy := methodValueCall - code := **(**uintptr)(unsafe.Pointer(&dummy)) - - fv := &methodValue{ - fn: code, - method: int(v.flag) >> flagMethodShift, - rcvr: rcvr, - } - - // Cause panic if method is not appropriate. - // The panic would still happen during the call if we omit this, - // but we want Interface() and other operations to fail early. - methodReceiver(op, fv.rcvr, fv.method) - - return Value{funcType, unsafe.Pointer(fv), 0, v.flag&flagRO | flag(Func)<<flagKindShift} -} - -// methodValueCall is an assembly function that is the code half of -// the function returned from makeMethodValue. It expects a *methodValue -// as its context register, and its job is to invoke callMethod(ctxt, frame) -// where ctxt is the context register and frame is a pointer to the first -// word in the passed-in argument frame. -func methodValueCall() |