Compare single QString against many, evaluate to true if it matches any

[Ewan Green]

If I wanted to compare 1 string against any string in a list at once, what could I do besides QStringList::contains()?
Logically, there's always the ability to test the strings one at a time, but Qt's extensive conveniences for strings makes me think there has to be a "better" (more convenient) way.

Looking for something like this:
if(str1 == QString(str2 || str3 || str4))
Could be inclusive or (|), comma, etc.. I just don't know what to look for.

[SGaist]

Hi,

What kind of string are you using for the comparison ?
How long can that list be ?

[Ewan Green]

QString. Ideally, the list could be as long as I want, i.e. a variadic static method or something

[SGaist]

What I meant is the content of the string not the object type :-)

[Ewan Green]

@SGaist I suppose they would all have to be the same length for the comparison to work properly.

[JonB]

@Ewan-Green said in Compare single QString against many, evaluate to true if it matches any:

if(str1 == QString(str2 || str3 || str4))

With this intention/syntax, makes me think of regular expression (use QRegularExpression): (str2|str3|str4). I guess it's one way of reducing typing a bit. This is only for literals, as per your code, unless you meant variables, but QString(str2 || str3 || str4) does not imply that to me.

[SGaist]

If it's an exact match you are looking for then QStringList::indexOf looks like what you want.

If you want it search whether there's an occurrence of your string within an entry of the list then using this overload with a simple regexp should do the trick.

And no there's no need for the strings to be all the same length.

[Kent-Dorfman]

if using a static or pre-loaded list of strings then create a map and compare your input string against the map keys using map::find(). Your search times will generally be much shorter. the general mechanism here is to use a binary search of a sorted list to determine if your input string is found.