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<html><head><title>dlib C++ Library - any_function_abstract.h</title></head><body bgcolor='white'><pre> |
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<font color='#009900'>// Copyright (C) 2011 Davis E. King (davis@dlib.net) |
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</font><font color='#009900'>// License: Boost Software License See LICENSE.txt for the full license. |
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</font><font color='#0000FF'>#undef</font> DLIB_AnY_FUNCTION_ABSTRACT_H_ |
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<font color='#0000FF'>#ifdef</font> DLIB_AnY_FUNCTION_ABSTRACT_H_ |
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<font color='#0000FF'>#include</font> "<a style='text-decoration:none' href='any_abstract.h.html'>any_abstract.h</a>" |
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<font color='#0000FF'>#include</font> "<a style='text-decoration:none' href='../algs.h.html'>../algs.h</a>" |
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<font color='#0000FF'>namespace</font> dlib |
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<b>{</b> |
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<font color='#009900'>// ---------------------------------------------------------------------------------------- |
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</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font> |
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<font color='#0000FF'>typename</font> function_type |
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<font color='#5555FF'>></font> |
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<font color='#0000FF'>class</font> <b><a name='any_function'></a>any_function</b> |
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<b>{</b> |
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<font color='#009900'>/*! |
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REQUIREMENTS ON function_type |
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This type should be a function signature. Some examples are: |
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void (int,int) // a function returning nothing and taking two ints |
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void () // a function returning nothing and taking no arguments |
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char (double&) // a function returning a char and taking a reference to a double |
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The number of arguments in the function must be no greater than 10. |
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INITIAL VALUE |
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- is_empty() == true |
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- for all T: contains<T>() == false |
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WHAT THIS OBJECT REPRESENTS |
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This object is a version of dlib::any that is restricted to containing |
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elements which are some kind of function object with an operator() which |
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matches the function signature defined by function_type. |
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Here is an example: |
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#include <iostream> |
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#include <string> |
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#include "dlib/any.h" |
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using namespace std; |
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void print_message(string str) { cout << str << endl; } |
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int main() |
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{ |
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dlib::any_function<void(string)> f; |
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f = print_message; |
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f("hello world"); // calls print_message("hello world") |
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} |
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Note that any_function objects can be used to store general function |
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objects (i.e. defined by a class with an overloaded operator()) in |
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addition to regular global functions. |
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!*/</font> |
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<font color='#0000FF'>public</font>: |
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<font color='#009900'>// This is the type of object returned by function_type functions. |
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</font> <font color='#0000FF'>typedef</font> result_type_for_function_type result_type; |
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<font color='#009900'>// Typedefs defining the argument types. If an argument does not exist |
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</font> <font color='#009900'>// then it is set to void. |
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</font> <font color='#0000FF'>typedef</font> type_of_first_argument_in_funct_type arg1_type; |
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<font color='#0000FF'>typedef</font> type_of_second_argument_in_funct_type arg2_type; |
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... |
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<font color='#0000FF'>typedef</font> type_of_last_argument_in_funct_type arg10_type; |
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<font color='#0000FF'>const</font> <font color='#0000FF'>static</font> <font color='#0000FF'><u>unsigned</u></font> <font color='#0000FF'><u>long</u></font> num_args <font color='#5555FF'>=</font> total_number_of_non_void_arguments; |
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<b><a name='any_function'></a>any_function</b><font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- this object is properly initialized |
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!*/</font> |
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<b><a name='any_function'></a>any_function</b> <font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> any_function<font color='#5555FF'>&</font> item |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- copies the state of item into *this. |
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- Note that *this and item will contain independent copies of the |
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contents of item. That is, this function performs a deep |
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copy and therefore does not result in *this containing |
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any kind of reference to item. |
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!*/</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font> <font color='#0000FF'>typename</font> T <font color='#5555FF'>></font> |
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<b><a name='any_function'></a>any_function</b> <font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> T<font color='#5555FF'>&</font> item |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- #contains<T>() == true |
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- #cast_to<T>() == item |
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(i.e. a copy of item will be stored in *this) |
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!*/</font> |
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<font color='#0000FF'><u>void</u></font> <b><a name='clear'></a>clear</b> <font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- #*this will have its default value. I.e. #is_empty() == true |
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!*/</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font><font color='#0000FF'>typename</font> T<font color='#5555FF'>></font> |
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<font color='#0000FF'><u>bool</u></font> <b><a name='contains'></a>contains</b> <font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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ensures |
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- if (this object currently contains an object of type T) then |
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- returns true |
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- else |
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- returns false |
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!*/</font> |
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<font color='#0000FF'><u>bool</u></font> <b><a name='is_empty'></a>is_empty</b><font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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ensures |
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- if (this object contains any kind of object) then |
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- returns false |
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- else |
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- returns true |
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!*/</font> |
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<font color='#0000FF'><u>bool</u></font> <b><a name='is_set'></a>is_set</b> <font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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ensures |
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- returns !is_empty() |
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!*/</font> |
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result_type <b><a name='operator'></a>operator</b><font face='Lucida Console'>(</font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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requires |
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- is_empty() == false |
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- the signature defined by function_type takes no arguments |
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ensures |
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- Let F denote the function object contained within *this. Then |
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this function performs: |
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return F() |
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or if result_type is void then this function performs: |
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F() |
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!*/</font> |
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result_type <b><a name='operator'></a>operator</b><font face='Lucida Console'>(</font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> arg1_type<font color='#5555FF'>&</font> a1 |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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requires |
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- is_empty() == false |
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- the signature defined by function_type takes one argument |
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ensures |
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- Let F denote the function object contained within *this. Then |
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this function performs: |
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return F(a1) |
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or if result_type is void then this function performs: |
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F(a1) |
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!*/</font> |
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result_type <b><a name='operator'></a>operator</b><font face='Lucida Console'>(</font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> arg1_type<font color='#5555FF'>&</font> a1, |
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<font color='#0000FF'>const</font> arg2_type<font color='#5555FF'>&</font> a2 |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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requires |
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- is_empty() == false |
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- the signature defined by function_type takes two arguments |
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ensures |
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- Let F denote the function object contained within *this. Then |
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this function performs: |
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return F(a1,a2) |
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or if result_type is void then this function performs: |
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F(a1,a2) |
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!*/</font> |
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<font color='#009900'>/* !!!!!!!!! NOTE !!!!!!!!! |
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In addition to the above, operator() is defined for up to 10 arguments. |
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They are not listed here because it would clutter the documentation. |
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!!!!!!!!! NOTE !!!!!!!!! */</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font><font color='#0000FF'>typename</font> T<font color='#5555FF'>></font> |
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T<font color='#5555FF'>&</font> <b><a name='cast_to'></a>cast_to</b><font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- if (contains<T>() == true) then |
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- returns a non-const reference to the object contained within *this |
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- else |
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- throws bad_any_cast |
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!*/</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font><font color='#0000FF'>typename</font> T<font color='#5555FF'>></font> |
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<font color='#0000FF'>const</font> T<font color='#5555FF'>&</font> <b><a name='cast_to'></a>cast_to</b><font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font> <font color='#0000FF'>const</font>; |
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<font color='#009900'>/*! |
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ensures |
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- if (contains<T>() == true) then |
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- returns a const reference to the object contained within *this |
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- else |
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- throws bad_any_cast |
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!*/</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font><font color='#0000FF'>typename</font> T<font color='#5555FF'>></font> |
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T<font color='#5555FF'>&</font> <b><a name='get'></a>get</b><font face='Lucida Console'>(</font> |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- #is_empty() == false |
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- #contains<T>() == true |
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- if (contains<T>() == true) |
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- returns a non-const reference to the object contained in *this. |
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- else |
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- Constructs an object of type T inside *this |
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- Any previous object stored in this any_function object is destructed and its |
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state is lost. |
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- returns a non-const reference to the newly created T object. |
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!*/</font> |
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any_function<font color='#5555FF'>&</font> <b><a name='operator'></a>operator</b><font color='#5555FF'>=</font> <font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> any_function<font color='#5555FF'>&</font> item |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- copies the state of item into *this. |
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- Note that *this and item will contain independent copies of the |
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contents of item. That is, this function performs a deep |
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copy and therefore does not result in *this containing |
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any kind of reference to item. |
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!*/</font> |
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<font color='#0000FF'><u>void</u></font> <b><a name='swap'></a>swap</b> <font face='Lucida Console'>(</font> |
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any_function<font color='#5555FF'>&</font> item |
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<font face='Lucida Console'>)</font>; |
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<font color='#009900'>/*! |
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ensures |
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- swaps *this and item |
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!*/</font> |
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<b>}</b>; |
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<font color='#009900'>// ---------------------------------------------------------------------------------------- |
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</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font> |
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<font color='#0000FF'>typename</font> function_type |
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<font color='#5555FF'>></font> |
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<font color='#0000FF'>inline</font> <font color='#0000FF'><u>void</u></font> <b><a name='swap'></a>swap</b> <font face='Lucida Console'>(</font> |
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any_function<font color='#5555FF'><</font>function_type<font color='#5555FF'>></font><font color='#5555FF'>&</font> a, |
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any_function<font color='#5555FF'><</font>function_type<font color='#5555FF'>></font><font color='#5555FF'>&</font> b |
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<font face='Lucida Console'>)</font> <b>{</b> a.<font color='#BB00BB'>swap</font><font face='Lucida Console'>(</font>b<font face='Lucida Console'>)</font>; <b>}</b> |
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<font color='#009900'>/*! |
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provides a global swap function |
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!*/</font> |
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<font color='#009900'>// ---------------------------------------------------------------------------------------- |
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</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font> |
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<font color='#0000FF'>typename</font> T, |
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<font color='#0000FF'>typename</font> function_type |
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<font color='#5555FF'>></font> |
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T<font color='#5555FF'>&</font> <b><a name='any_cast'></a>any_cast</b><font face='Lucida Console'>(</font> |
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any_function<font color='#5555FF'><</font>function_type<font color='#5555FF'>></font><font color='#5555FF'>&</font> a |
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<font face='Lucida Console'>)</font> <b>{</b> <font color='#0000FF'>return</font> a.cast_to<font color='#5555FF'><</font>T<font color='#5555FF'>></font><font face='Lucida Console'>(</font><font face='Lucida Console'>)</font>; <b>}</b> |
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<font color='#009900'>/*! |
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ensures |
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- returns a.cast_to<T>() |
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!*/</font> |
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<font color='#009900'>// ---------------------------------------------------------------------------------------- |
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</font> |
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<font color='#0000FF'>template</font> <font color='#5555FF'><</font> |
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<font color='#0000FF'>typename</font> T, |
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<font color='#0000FF'>typename</font> function_type |
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<font color='#5555FF'>></font> |
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<font color='#0000FF'>const</font> T<font color='#5555FF'>&</font> <b><a name='any_cast'></a>any_cast</b><font face='Lucida Console'>(</font> |
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<font color='#0000FF'>const</font> any_function<font color='#5555FF'><</font>function_type<font color='#5555FF'>></font><font color='#5555FF'>&</font> a |
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<font face='Lucida Console'>)</font> <b>{</b> <font color='#0000FF'>return</font> a.cast_to<font color='#5555FF'><</font>T<font color='#5555FF'>></font><font face='Lucida Console'>(</font><font face='Lucida Console'>)</font>; <b>}</b> |
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<font color='#009900'>/*! |
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ensures |
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- returns a.cast_to<T>() |
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!*/</font> |
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<font color='#009900'>// ---------------------------------------------------------------------------------------- |
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</font> |
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<b>}</b> |
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<font color='#0000FF'>#endif</font> <font color='#009900'>// DLIB_AnY_FUNCTION_ABSTRACT_H_ |
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</font> |
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</pre></body></html> |
