How to Construct a Std::String With Embedded Values, I.E. "String Interpolation"

Simplest syntax for string interpolation in c++

From c++20 you can use the <format> header to do something like this:

auto s = std::format("My variable has value {}", myVariable);

which is quite similar to how it's done in c# or JavaScript.

How to give html tags inside string interpolation in reactjs?

I did like this and the translation are working fine now. Because I am working on multilingual app. Translations are needed.

const getConfirmMsg= (card, isDelete) => {
       const valueType = getValue(card);
    
        const confirmMessage = isDelete ? (
              <>
              <p>{tr(`You are about to delete the`)} <i>{tr( valueType)}</i> .
              </p>
              <p>{tr(` This is the last value.`)}</p>
              </>
          ) : (
            tr(`All selected values will be removed.`)
          );

return (confirmMessage);
};

How does string interpolation / string templates work?

There are two options for string interpolation in Vala and Genie:

1. printf-style functions:

   var name = "Jens Mühlenhoff";
   var s = string.printf ("My name is %s, 2 + 2 is %d", name, 2 + 2);
   

   This works using varargs, you have to pass multiple arguments with the correct types to the varargs function (in this case string.printf).

2. string templates:

   var name = "Jens Mühlenhoff";
   var s = @"My name is $name, 2 + 2 is $(2 + 2)";
   

   This works using "compiler magic".

   A template string starts with @" (rather then " which starts a normal string).

   Expressions in the template string start with $ and are enclosed with (). The brackets are unneccesary when the expression doesn't contain white space like $name in the above example.

   Expressions are evaluated before they are put into the string that results from the string template. For expressions that aren't of type string the compiler tries to call .to_string (), so you don't have to explicitly call it. In the $(2 + 2) example the expression 2 + 2 is evaluated to 4 and then 4.to_string () is called with will result in "4" which can then be put into the string template.

PS: I'm using Vala syntax here, just remove the ;s to convert to Genie.

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