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Re: Trees using Inline::C

by esskar (Deacon)
on Aug 01, 2005 at 00:03 UTC ( #479756=note: print w/replies, xml ) Need Help??


in reply to Trees using Inline::C

SV* get_parent(SV* obj) { Node *node = (Node *)SvIV(SvRV(obj)); if(node != NULL && node->parent != NULL) return new( "Node", node->parent->name, node->parent->desc, node->parent->branch_length ); else return NULL; // not sure }
but i would prefer to set parent to NULL inside the new function, and add an iditional member named "class" to your struct treeNode to ensure the same class name

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Re^2: Trees using Inline::C
by rvosa (Curate) on Aug 01, 2005 at 00:31 UTC
    Thanks for your reply! But, is that efficient memory usage? Memory has already been allocated when:
    my $parent = Node->new('Homo_neanderthalensis', 'Hominid', 5.02);
    was called, and it seems like this new call to
    return new( /*..etc...*/);
    goes the same route? Or am I missing something? Thanks again!
      sure. you are right; but see, a (Node *) has no information about its (SV *). A workaround would be
      typedef struct treeNode { char* name; char* desc; char* class; //in case we need it double branch_length; SV* obj; // the perlobj SV* obj_ref; // the ref to the perlobj struct treeNode *parent; } Node; SV* new(char* class, char* name, char* desc, double branch_length) { Node* node = malloc(sizeof(Node)); node->obj_ref = newSViv(0); node->obj = newSVrv(obj_ref, class); node->class = savepv(class); node->name = savepv(name); node->desc = savepv(desc); node->branch_length = branch_length; node->parent = NULL; // no parent yet sv_setiv(node->obj, (IV)node); SvREADONLY_on(node->obj); return node->obj_ref; } SV* get_parent(SV* obj) { Node *node = (Node *)SvIV(SvRV(obj)); if(node != NULL && node->parent != NULL) return node->parent->obj_ref; else return NULL; // not sure }
      HTH
        Thanks eskar! Will give that a try.

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