When C ++ is overloaded, non-module functions are preferentially matched.

It is found that when there are enough overload functions,

When a non-module function or a module function can be matched,

GCC seems to give priority to non-module functions.

See the followingCode

# Include <iostream> # Include <Vector> # Include < String > # Include <Limits> Using   Namespace  STD;  Int Max ( Const   Int N1, Const  Int  N2 ){  Return N1> N2? N1: N2 ;}  Float Max ( Const   Float F1, Const   Float  F2 ){  Return F1> F2? F1: F2 ;}  String Max ( Const   String Str1,Const    String  Str2 ){  Return Str1> str2? Str1: str2 ;}  # If 0 Int Max ( Const Vector < Int > & VEC ){  Return * Max_element (VEC. Begin (), VEC. End ());}  Float Max ( Const Vector < Float > & VEC ){  Return * Max_element (VEC. Begin (), VEC. End ());}  String Max ( Const Vector < String > & VEC ){  Return * Max_element (VEC. Begin (), VEC. End ());}  Int Max ( Const   Int * Array,Int  Size ){  Int Int_max = numeric_limits < Int > : Min ();  For ( Int I = 0 ; I <size; ++ I) {int_max = Max (int_max, array [I]);}  Return  Int_max ;}  Float Max ( Const  Float * Array, Int  Size ){  Float Float_max = numeric_limits < Float > : Min ();  For ( Int I = 0 ; I <size; ++ I) {float_max = Max (float_max, array [I]);}  Return  Float_max ;} String Max ( Const   String * Array, Int  Size ){  Return * Max_element (array, array + Size );}  # Endif  Template <Typename T> T max (  Const Vector <t> & VEC) {cout < "  Invoke " < Endl;  Return * Max_element (VEC. Begin (), VEC. End ();} Template <Typename T> T max (  Const T * array, Int  Size ){  Return * Max_element (array, array + Size );}  Int Main ( Int Argc, Const  Char * Argv []) {cout < "  Test overload Max  " < Endl;  Int N1 = 3  ;  Int N2 = 9  ;  Float F1 = 3.14  ; Float F2 = 98.44  ;  String Str1 = "  S1  "  ;  String Str2 = "  ABC  "  ; Cout < "  Max int (  " <N1 < "   " <N2 < "  )  " <Max (N1, N2) < Endl < "  Max float (  " <F1 < "   " <F2 < "  )  " <Max (F1, F2) < Endl < "  Max string (  " <Str1 < "   " <Str2 < "  )  " < Max (str1, str2) < Endl;  Int Int_array [] = {33 , 444 , 5 , 322 , 124 , 55 , 3436  }; Vector < Int > Int_vec (int_array, int_array + Sizeof (Int_array )/ Sizeof ( Int  ); Cout <"  The Max number of the int vector is:  " <Max (int_vec) < Endl;  Float F_array [] = { 34.24 , 4324.43 , 9999.43 , 556.34  }; Vector < Float > F_vec (f_array, f_array + Sizeof (F_array )/ Sizeof ( Float  ); Cout < "  The Max number of the float vector is:  " <Max (f_vec) < Endl;  String Str_array [] = { "  Boog  " , "  Gogod  " , " Zero  " , "  Loe  " , "  Abcdasdfas  "  ,  " Please refer to the following link for more information:"  }; Vector < String > Str_vec (str_array, str_array + Sizeof (Str_array )/ Sizeof ( String  ); Cout < "  The max number of the string vector is:  " <Max (str_vec) < Endl;  # If 1 Cout <"  The Max number of the int array is:  " <Max (int_array, Sizeof (Int_array )/ Sizeof ( Int ) < Endl; cout < "  The max number of the flaot array is:  " <Max (f_array, Sizeof (F_array )/ Sizeof (Float ) < Endl; cout < "  The Max number of the string array is:  " <Max (str_array, Sizeof (Str_array )/ Sizeof (Str_array [ 0  ]) < "  Sizes =  " < Sizeof (Str_array )/Sizeof (Str_array [ 0  ]) < "  Sizes of str_array  " < Sizeof  (Str_array) < "  Sizes of str_array [0]  " < Sizeof (Str_array [ 0  ]) < Endl;  # Endif      Return   0  ;} 

Output

Test overload Max
Max int (3 9) 9
Max float (3.14 98.44) 98.44
Max string (S1 ABC) S1
Invoke
The Max number of the int vector is: 3436
Invoke
The Max number of the float vector is: 9999.43
Invoke
The max number of the string vector is: Zero
The Max number of the int array is: 3436
The max number of the flaot array is: 9999.43
The Max number of the string array is: Zero sizes = 6 sizes of str_array 24 sizes of str_array [0] 4

 

 

If # If 0 is enabled, no non-module function is called by invoke.