Re: creating a custom named variable with a function

From:
Maciej Sobczak <no.spam@no.spam.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Tue, 17 Apr 2007 09:52:54 CST
Message-ID:
<f02m16$6pm$1@cernne03.cern.ch>
Hi,

Justcallmedrago@yahoo.com wrote:

How would you declare and assign a variable inside a function?
*the variable must end up having the name as the parameter
*i don't want to declare the variable before i call the function.


You cannot do this the direct way.

example:
when you call createvariable("eggroll")

it will declare the variable "eggroll"
and then maybe assign it something.
eggroll = "this is a real variable"

also so you can use it later, outside of the function.


You cannot make it a variable in the C++ sense of this word, but you can
use some global dictionary (a map to be precise) which will serve the
same purpose:

std::map<std::string, std::string> myVariables;

and then:

void createVariable(const std::string &varName)
{
     myVariables[varName] = "this is a real variable";
}

so that after calling:

createVariable("eggroll");

you can read (use) it, for example:

std::cout << myVariables["eggroll"];

If you like this idea, you will also like boost::any.

--
Maciej Sobczak : http://www.msobczak.com/
Programming : http://www.msobczak.com/prog/

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