From aca4b1ad122434458125b4f25ea2d99a80370ee4 Mon Sep 17 00:00:00 2001
From: Artur Artamonov <freeartman@wechall.net>
Date: Sun, 17 Aug 2014 19:40:06 +0100
Subject: Initial commit

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++------------------------------------------------------------------------------+
++                                                                              +
++------------------------------------------------------------------------------+
++                            C11 _Generic                                      +
++------------------------------------------------------------------------------+
++                                                                              +
++------------------------------------------------------------------------------+
++                            INDEX                                             +
++------------------------------------------------------------------------------+
+
+1. Intro
+2. Examples
+	2.1. Detect type
+	2.2. Check if types is compatible
+3. Tested
+4. Links
+5. Files
+
++------------------------------------------------------------------------------+
++                            1.INTRO                                           +
++------------------------------------------------------------------------------+
+        In C standard c11 is supported new keyword _Generic. It add way how 
+we can add at macro level decisions about variable types. And now is 
+possible make some C++ like function "overloading". Here is some variants how
+to use this generic "_Generic". Now could print variables dont looking
+on its type _Generic will deal with it. 
+
++------------------------------------------------------------------------------+
++                            2.EXAMPLES                                        +
++------------------------------------------------------------------------------+
+2.1.Detect type
+
+
+
+  #define type_str(T) _Generic( (T), int: "int",\
+  long: "long",\
+  default: "Unknown type")
+
+Now we have define check for 2 types int and long. If there is some type
+undefined then choose default type and print "Unknown type". This is auto
+printf example where you can detect type and print its name. But as in page [1]
+you can add number values and compare types in simple way.
+
+  printf("Type1 %s\n", type_str('a'));
+  printf("Type2 %s\n", type_str(1));
+  printf("Type3 %s\n", type_str(1l));
+  printf("Type4 %s\n", type_str(0.0f));
+
+
+Also is possible to use generic for 2 or more types but then amount
+of declaration grows. But it means that now according to params
+we can choose best function.
+
+  #define type_str2(T1,T2) _Generic( (T1),\
+  int: _Generic((T2),int:"int int", default: "int UNK"),\
+  default: "UNK UNK" )
+
+  printf("Double Type 1 %s\n", type_str2(1,1));
+  printf("Double Type 2 %s\n", type_str2(1,0.0f));
+  printf("Double Type 3 %s\n", type_str2(.0f,.0f));
+
+
++------------------------------------------------------------------------------+
+2.2.Check if types is compatible
+
+Strange but some types could be invalid if there is const used, like 
+'int' and 'const int'. 
+
+  #define is_compatible(x,T) _Generic((x), T:"compatible",\
+  default: "non-compatible")
+
+Here is defined 2 types and only (int and int) and (const int and const int)
+is compatible.
+
+  int i1;
+  const int i2;
+  printf("int       == int,       %s\n", is_compatible(i1,int));
+  printf("const int == const int, %s\n", is_compatible(i2,const int));
+  printf("int       == const int, %s\n", is_compatible(i1,const int));
+  printf("const int == int,       %s\n", is_compatible(i2,int));
+
+
+
++------------------------------------------------------------------------------+
++                            3.TESTED                                          +
++------------------------------------------------------------------------------+
+gcc-4.9.1
+clang-3.4
+
+
++------------------------------------------------------------------------------+
++                            4.LINKS                                           +
++------------------------------------------------------------------------------+
+[1] http://www.robertgamble.net/2012/01/c11-generic-selections.html
+[2] http://en.wikipedia.org/wiki/C11_%28C_standard_revision%29
+[3] https://gcc.gnu.org/wiki/C11Status
+
++------------------------------------------------------------------------------+
++                            5.FILES                                           +
++------------------------------------------------------------------------------+
+ex1.c  -  one argument generic
+ex2.c  -  two argument generic
+ex3.c  -  check for compatibility
+>base64 source.tar.gz
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