mirror of
https://github.com/ecency/ecency-mobile.git
synced 2024-12-23 05:13:04 +03:00
297 lines
9.8 KiB
C++
297 lines
9.8 KiB
C++
////////////////////////////////////////////////////////////////////////////
|
|
// lazy_reuse.hpp
|
|
//
|
|
// Build lazy operations for Phoenix equivalents for FC++
|
|
//
|
|
// These are equivalents of the Boost FC++ functoids in reuse.hpp
|
|
//
|
|
// Implemented so far:
|
|
//
|
|
// reuser1
|
|
// reuser2
|
|
// reuser3
|
|
// reuser4 (not yet tested)
|
|
//
|
|
// NOTE: It has been possible to simplify the operation of this code.
|
|
// It now makes no use of boost::function or old FC++ code.
|
|
//
|
|
// The functor type F must be an operator defined with
|
|
// boost::phoenix::function.
|
|
// See the example Apply in lazy_prelude.hpp
|
|
//
|
|
////////////////////////////////////////////////////////////////////////////
|
|
/*=============================================================================
|
|
Copyright (c) 2000-2003 Brian McNamara and Yannis Smaragdakis
|
|
Copyright (c) 2001-2007 Joel de Guzman
|
|
Copyright (c) 2015 John Fletcher
|
|
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
==============================================================================*/
|
|
|
|
#ifndef BOOST_PHOENIX_FUNCTION_LAZY_REUSE
|
|
#define BOOST_PHOENIX_FUNCTION_LAZY_REUSE
|
|
|
|
#include <boost/phoenix/core.hpp>
|
|
#include <boost/phoenix/function.hpp>
|
|
#include <boost/intrusive_ptr.hpp>
|
|
|
|
|
|
namespace boost {
|
|
|
|
namespace phoenix {
|
|
|
|
namespace fcpp {
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// Original FC++ comment:
|
|
// "Reuser"s are effectively special-purpose versions of curry() that
|
|
// enable recursive list functoids to reuse the thunk of the curried
|
|
// recursive call. See
|
|
// http://www.cc.gatech.edu/~yannis/fc++/New/reusers.html
|
|
// for a more detailed description.
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
// For efficiency, we mark parameters as either "VAR"iant or "INV"ariant.
|
|
struct INV {};
|
|
struct VAR {};
|
|
|
|
template <class V, class X> struct Maybe_Var_Inv;
|
|
template <class X>
|
|
struct Maybe_Var_Inv<VAR,X> {
|
|
static void remake( X& x, const X& val ) {
|
|
x.~X();
|
|
new (&x) X(val);
|
|
}
|
|
static X clone( const X& x ) { return X(x); }
|
|
};
|
|
template <class X>
|
|
struct Maybe_Var_Inv<INV,X> {
|
|
static void remake( X&, const X& ) {}
|
|
static const X& clone( const X& x ) { return x; }
|
|
};
|
|
|
|
/////////////////////////////////////////////////////////////////////
|
|
// ThunkImpl is an implementation of Fun0Impl for this use.
|
|
/////////////////////////////////////////////////////////////////////
|
|
|
|
template <class Result>
|
|
class ThunkImpl
|
|
{
|
|
mutable RefCountType refC;
|
|
public:
|
|
ThunkImpl() : refC(0) {}
|
|
virtual Result operator()() const =0;
|
|
virtual ~ThunkImpl() {}
|
|
template <class X>
|
|
friend void intrusive_ptr_add_ref( const ThunkImpl<X>* p );
|
|
template <class X>
|
|
friend void intrusive_ptr_release( const ThunkImpl<X>* p );
|
|
};
|
|
|
|
template <class T>
|
|
void intrusive_ptr_add_ref( const ThunkImpl<T>* p ) {
|
|
++ (p->refC);
|
|
}
|
|
template <class T>
|
|
void intrusive_ptr_release( const ThunkImpl<T>* p ) {
|
|
if( !--(p->refC) ) delete p;
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// reuser1 is needed in list<T> operations
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
template <class V1, class V2, class F, class X>
|
|
struct reuser1;
|
|
|
|
template <class V1, class V2, class F, class X, class R>
|
|
struct Thunk1 : public ThunkImpl<R> {
|
|
mutable F f;
|
|
mutable X x;
|
|
Thunk1( const F& ff, const X& xx ) : f(ff), x(xx) {}
|
|
void init( const F& ff, const X& xx ) const {
|
|
Maybe_Var_Inv<V1,F>::remake( f, ff );
|
|
Maybe_Var_Inv<V2,X>::remake( x, xx );
|
|
}
|
|
R operator()() const {
|
|
return Maybe_Var_Inv<V1,F>::clone(f)(
|
|
Maybe_Var_Inv<V2,X>::clone(x),
|
|
reuser1<V1,V2,F,X>(this) );
|
|
}
|
|
};
|
|
|
|
template <class V1, class V2, class F, class X>
|
|
struct reuser1 {
|
|
typedef typename F::template result<F(X)>::type R;
|
|
typedef typename boost::phoenix::function<R> fun0_type;
|
|
typedef Thunk1<V1,V2,F,X,R> M;
|
|
typedef M result_type;
|
|
boost::intrusive_ptr<const M> ref;
|
|
reuser1(a_unique_type_for_nil) {}
|
|
reuser1(const M* m) : ref(m) {}
|
|
M operator()( const F& f, const X& x ) {
|
|
if( !ref ) ref = boost::intrusive_ptr<const M>( new M(f,x) );
|
|
else ref->init(f,x);
|
|
return *ref;
|
|
}
|
|
void iter( const F& f, const X& x ) {
|
|
if( ref ) ref->init(f,x);
|
|
}
|
|
};
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// reuser2 is needed in list<T>
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
template <class V1, class V2, class V3, class F, class X, class Y>
|
|
struct reuser2;
|
|
|
|
template <class V1, class V2, class V3, class F, class X, class Y, class R>
|
|
struct Thunk2 : public ThunkImpl<R> {
|
|
mutable F f;
|
|
mutable X x;
|
|
mutable Y y;
|
|
Thunk2( const F& ff, const X& xx, const Y& yy ) : f(ff), x(xx), y(yy) {}
|
|
void init( const F& ff, const X& xx, const Y& yy ) const {
|
|
Maybe_Var_Inv<V1,F>::remake( f, ff );
|
|
Maybe_Var_Inv<V2,X>::remake( x, xx );
|
|
Maybe_Var_Inv<V3,Y>::remake( y, yy );
|
|
}
|
|
R operator()() const {
|
|
return Maybe_Var_Inv<V1,F>::clone(f)(
|
|
Maybe_Var_Inv<V2,X>::clone(x),
|
|
Maybe_Var_Inv<V3,Y>::clone(y),
|
|
reuser2<V1,V2,V3,F,X,Y>(this) );
|
|
}
|
|
};
|
|
|
|
template <class V1, class V2, class V3, class F, class X, class Y>
|
|
struct reuser2 {
|
|
typedef typename F::template result<F(X,Y)>::type R;
|
|
typedef Thunk2<V1,V2,V3,F,X,Y,R> M;
|
|
typedef M result_type;
|
|
boost::intrusive_ptr<const M> ref;
|
|
reuser2(a_unique_type_for_nil) {}
|
|
reuser2(const M* m) : ref(m) {}
|
|
M operator()( const F& f, const X& x, const Y& y ) {
|
|
if( !ref ) ref = boost::intrusive_ptr<const M>( new M(f,x,y) );
|
|
else ref->init(f,x,y);
|
|
return *ref;
|
|
}
|
|
void iter( const F& f, const X& x, const Y& y ) {
|
|
if( ref ) ref->init(f,x,y);
|
|
}
|
|
};
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// reuser3
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
template <class V1, class V2, class V3, class V4,
|
|
class F, class X, class Y, class Z>
|
|
struct reuser3;
|
|
|
|
template <class V1, class V2, class V3, class V4,
|
|
class F, class X, class Y, class Z, class R>
|
|
struct Thunk3 : public ThunkImpl<R> {
|
|
mutable F f;
|
|
mutable X x;
|
|
mutable Y y;
|
|
mutable Z z;
|
|
Thunk3( const F& ff, const X& xx, const Y& yy, const Z& zz )
|
|
: f(ff), x(xx), y(yy), z(zz) {}
|
|
void init( const F& ff, const X& xx, const Y& yy, const Z& zz ) const {
|
|
Maybe_Var_Inv<V1,F>::remake( f, ff );
|
|
Maybe_Var_Inv<V2,X>::remake( x, xx );
|
|
Maybe_Var_Inv<V3,Y>::remake( y, yy );
|
|
Maybe_Var_Inv<V4,Z>::remake( z, zz );
|
|
}
|
|
R operator()() const {
|
|
return Maybe_Var_Inv<V1,F>::clone(f)(
|
|
Maybe_Var_Inv<V2,X>::clone(x),
|
|
Maybe_Var_Inv<V3,Y>::clone(y),
|
|
Maybe_Var_Inv<V4,Z>::clone(z),
|
|
reuser3<V1,V2,V3,V4,F,X,Y,Z>(this) );
|
|
}
|
|
};
|
|
|
|
template <class V1, class V2, class V3, class V4,
|
|
class F, class X, class Y, class Z>
|
|
struct reuser3 {
|
|
typedef typename F::template result<F(X,Y,Z)>::type R;
|
|
typedef Thunk3<V1,V2,V3,V4,F,X,Y,Z,R> M;
|
|
typedef M result_type;
|
|
boost::intrusive_ptr<const M> ref;
|
|
reuser3(a_unique_type_for_nil) {}
|
|
reuser3(const M* m) : ref(m) {}
|
|
M operator()( const F& f, const X& x, const Y& y, const Z& z ) {
|
|
if( !ref ) ref = boost::intrusive_ptr<const M>( new M(f,x,y,z) );
|
|
else ref->init(f,x,y,z);
|
|
return *ref;
|
|
}
|
|
void iter( const F& f, const X& x, const Y& y, const Z& z ) {
|
|
if( ref ) ref->init(f,x,y,z);
|
|
}
|
|
};
|
|
//////////////////////////////////////////////////////////////////////
|
|
// reuser4
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
template <class V1, class V2, class V3, class V4, class V5,
|
|
class F, class W, class X, class Y, class Z>
|
|
struct reuser4;
|
|
|
|
template <class V1, class V2, class V3, class V4, class V5,
|
|
class F, class W, class X, class Y, class Z, class R>
|
|
struct Thunk4 : public ThunkImpl<R> {
|
|
mutable F f;
|
|
mutable W w;
|
|
mutable X x;
|
|
mutable Y y;
|
|
mutable Z z;
|
|
Thunk4( const F& ff, const W& ww, const X& xx, const Y& yy, const Z& zz )
|
|
: f(ff), w(ww), x(xx), y(yy), z(zz) {}
|
|
void init( const F& ff, const W& ww, const X& xx, const Y& yy, const Z& zz ) const {
|
|
Maybe_Var_Inv<V1,F>::remake( f, ff );
|
|
Maybe_Var_Inv<V2,W>::remake( w, ww );
|
|
Maybe_Var_Inv<V3,X>::remake( x, xx );
|
|
Maybe_Var_Inv<V4,Y>::remake( y, yy );
|
|
Maybe_Var_Inv<V5,Z>::remake( z, zz );
|
|
}
|
|
R operator()() const {
|
|
return Maybe_Var_Inv<V1,F>::clone(f)(
|
|
Maybe_Var_Inv<V2,W>::clone(w),
|
|
Maybe_Var_Inv<V3,X>::clone(x),
|
|
Maybe_Var_Inv<V4,Y>::clone(y),
|
|
Maybe_Var_Inv<V5,Z>::clone(z),
|
|
reuser4<V1,V2,V3,V4,V5,F,W,X,Y,Z>(this) );
|
|
}
|
|
};
|
|
|
|
template <class V1, class V2, class V3, class V4, class V5,
|
|
class F, class W, class X, class Y, class Z>
|
|
struct reuser4 {
|
|
typedef typename F::template result<F(W,X,Y,Z)>::type R;
|
|
typedef Thunk4<V1,V2,V3,V4,V5,F,W,X,Y,Z,R> M;
|
|
typedef M result_type;
|
|
boost::intrusive_ptr<const M> ref;
|
|
reuser4(a_unique_type_for_nil) {}
|
|
reuser4(const M* m) : ref(m) {}
|
|
M operator()( const F& f, const W& w, const X& x, const Y& y, const Z& z ) {
|
|
if( !ref ) ref = boost::intrusive_ptr<const M>( new M(f,w,x,y,z) );
|
|
else ref->init(f,w,x,y,z);
|
|
return *ref;
|
|
}
|
|
void iter( const F& f, const W& w, const X& x, const Y& y, const Z& z ) {
|
|
if( ref ) ref->init(f,w,x,y,z);
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
#endif
|