C passing a char as a string into a function without defining the string-CodePudding

Consider a function

void foo(string s) {
...
}

I want to call the function as follows:

char ch = 'a';
foo(ch);

Of course it doesn't work as ch is a char and we need to convert it into a string.

I know I can do

char ch = 'a';
string str;
foo(str ch);

I do not want to declare string str beforehand, I want to do something during the function call itself to convert ch into string, like:

char ch = 'a';
foo(some_operation_on_ch);

Is it possible to do so, if yes, how?

CodePudding user response：

std::string has a constructor that takes a character and an integer for the number of times you what the character repeated. Using that you could do

foo(std::string(1, ch));

The class also has a constructor that takes c-style string and a integer denoting the number of characters to copy and you can use that constructor like

foo(std::string(&ch, 1));

CodePudding user response：

You can use:

char ch = 'a';
foo(std::string(1, ch));