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Convert blank string to reference

Posted on 2004-09-29
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Last Modified: 2010-04-01
I have a function which returns a reference to a string(std::string).  How do I go about returning a reference to a blank string if certain conditions are not met?
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Question by:jewee
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2 Comments
 
LVL 55

Expert Comment

by:Jaime Olivares
ID: 12181977
I guess you name "reference" to a pointer? That is:

std::string *SomeFunction(arguments here)

You can always return a NULL pointer if function fails, just

(inside function)
return NULL;

(outside function)
std::string *aString=SomeFunction(arguments here)

if (aString!=NULL) {
     // some action here
}
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LVL 86

Accepted Solution

by:
jkr earned 500 total points
ID: 12182024
>>How do I go about returning a reference to a blank string if certain conditions are not met?

A reference to a blank string is just the same as a reference to an empty string, e.g.

void GetQueryResults ( string& strQuery, string& strResults) {

    strResults = ""; // blank out string first, so we return an empty result set if nothing found

     // add results to strResults, if any

    // if nothing was would, strResult is set to empty/blank, i.e. strResults.size() == 0
    // and strResults.empty() == true
}
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