templates - C++ Invalid use of 'this' in non-member function -

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• invalid use of 'this' in non-member function 1 answer

i have error "invalid use of 'this' in non-member function"

what correct way write code avoid error.

tree.h:

#ifndef tree_h #define tree_h  template <typename t> class node;  class tree { public:     tree();      template <typename tnodetype>     node<tnodetype> elaborate(node<tnodetype> &node);      tree* self();      void dosomething(); };  template <typename tnodetype> node<tnodetype> createnew() {     node<tnodetype> model(this); //<-- error here     return model; }  #endif // tree_h 

node.h:

#ifndef node_h #define node_h  #include <tree.h>  template <typename tnodetype> class node { public:     node(tree *tree);      tnodetype current();  private:     tree *_tree; };  template <typename tnodetype> node<tnodetype>::node(tree *tree):     _tree(tree) {     _tree->dosomething(); }  template <typename tnodetype> tnodetype node<tnodetype>::current() {     //some code here }  #endif // node_h 

solved.

in tree.h skipped declaration of:

template <typename tnodetype> node<tnodetype> createnew(); 

and had forgotten in definition "tree::" before "createnew()"

i agree question have been avoided ;-). sorry

createnew() free function (i.e. not member of class), , therefore has no notion of this.