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/*
* Copyright © 2007,2008,2009,2010 Red Hat, Inc.
* Copyright © 2012,2018 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#ifndef HB_DISPATCH_HH
#define HB_DISPATCH_HH
#include "hb.hh"
/*
* Dispatch
*/
template <typename Context, typename Return=hb_empty_t, unsigned int MaxDebugDepth=0>
struct hb_dispatch_context_t
{
private:
/* https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern */
const Context* thiz () const { return static_cast<const Context *> (this); }
Context* thiz () { return static_cast< Context *> (this); }
public:
const char *get_name () { return "UNKNOWN"; }
static constexpr unsigned max_debug_depth = MaxDebugDepth;
typedef Return return_t;
template <typename T, typename F>
bool may_dispatch (const T *obj HB_UNUSED, const F *format HB_UNUSED) { return true; }
template <typename T, typename ...Ts>
return_t dispatch (const T &obj, Ts&&... ds)
{ return obj.dispatch (thiz (), hb_forward<Ts> (ds)...); }
static return_t no_dispatch_return_value () { return Context::default_return_value (); }
static bool stop_sublookup_iteration (const return_t r HB_UNUSED) { return false; }
unsigned debug_depth = 0;
};
#endif /* HB_DISPATCH_HH */
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