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Question on hash_map in stl

I want to use a hash_map to store some data. the key is going to be a const char* and the object is going to be a custom struct. I have no idea how to go about implementing this and I can't find anything online. I need to be pointed to a tutorial on using hash_maps. the one on sgis website doesn't help enough.

I am trying to call the following:

struct eqstr
      {
       bool operator()(const char* s1, const char* s2) const
      {
             return strcmp(s1, s2) == 0;
      }
      };
      hash_map<const char*, notes, hash<const char*>, eqstr> toolNotes;

and getting an error that hash is undefined.

_ys_

Perhaps this is what you intended:

hash_map<const char*, notes, hash_compare<const char*, eqstr> > toolNotes;

Assuming that 'notes' is defined as a type (e.g. class notes).

jjacksn

ASKER

Ok, that declaration works, but is says its deprecated. Do you know of anywhere I can read about or see sample code of hash_map. Not the sgi version, which is different.

efn

There isn't any hash_map in the standard library, so implementations may vary. Which one are you using?

This may help:

http://www.rpi.edu/~daiglm/plang/ml3.html

--efn

jjacksn

ASKER

I programming in VS.NET in C++. STL doesn't have a hash_map? I'm just using include <hash_map> Is there a better hash_map to use?

jjacksn

ASKER

Basically, I want to do the following:

Using a custom deifnied struct, store information about users keyed on their e-mail addresses. I will need to be accessing these over and over, updating the data, then finally outputing to an xml file. What is the best/easiest way to do this. I don't seem to be getting how use hashmap.

ASKER CERTIFIED SOLUTION

Axter

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