Illustrates how I think of Ruby's methods

method.c

#include <stdio.h>
#include <string.h>

typedef struct {
  char* name;
  int (*pointer)( int arg ); 
} Method;

typedef struct {
  Method* methods;
  int methods_size;
} Class;

typedef struct {
  Class* class;
} Object;

int twice(  int arg ) { return arg * 2; }
int thrice( int arg ) { return arg * 3; }

Method* method( Object *o , char* method_name ) {
  int i;
  for( i = 0 ; i < o->class->methods_size ; ++i )
    if( !strcmp( o->class->methods[i].name , method_name ) )
      return &o->class->methods[i];
  return NULL;
}

int main( ) {
  
  Method methods[] = { 
    { "twice"  , twice  },
    { "thrice" , thrice },
  };
  
  Class Multiplier = { 
    methods , 
    sizeof(methods)/sizeof(Method) 
  };
  
  Object multiplier = { &Multiplier };
  
  Method *my_meth = method( &multiplier , "twice"  );
  printf( "%s: %d\n" , my_meth->name , my_meth->pointer(1) );
  
  my_meth = method( &multiplier , "thrice"  );
  printf( "%s: %d\n" , my_meth->name , my_meth->pointer(1) );
  
  return 0;
}