How to create global function for all .JSLIB files?

I can't understand how to work with .jslib files. I don't understand the syntax of this type of file. Also I couldn't find any easy explanation of it

The problem started when I tried to make two functions global for all .jslib files:

/**
 * @param {string} str
 * @returns {string}
 */
function StrJSToStrCS (str) {
    const bufferSize = lengthBytesUTF8(str) + 1;
    const buffer = _malloc(bufferSize);
    stringToUTF8(str, buffer, bufferSize);
    return buffer;
}

/**
 * @param {string} str
 * @returns {string}
 */
function StrCSToStrJS (str) {
    return UTF8ToString(str);
}

What I already tried:

• To define these two functions in the same file

  function StrJSToStrCS (str) {
      const bufferSize = lengthBytesUTF8(str) + 1;
      const buffer = _malloc(bufferSize);
      stringToUTF8(str, buffer, bufferSize);
      return buffer;
  }
  
  function StrCSToStrJS (str) {
      return UTF8ToString(str);
  }
  
  const lib = {
      Hello: function () {
          return StrJSToStrCS('HELLO WORLD!');
      },
  
      ConsoleLog: function (str) {
          console.log(StrCSToStrJS(str));
      }
  };
  
  mergeInto(LibraryManager.library, lib);
  

• To define these two functions in script tag in .html after reading this. If it's important the script tag I inserted at the bottom of body tag

  <script>
      function StrJSToStrCS (str) {
          const bufferSize = lengthBytesUTF8(str) + 1;
          const buffer = _malloc(bufferSize);
          stringToUTF8(str, buffer, bufferSize);
          return buffer;
      }
  
      function StrCSToStrJS (str) {
          return UTF8ToString(str);
      }
  </script>
  

  const lib = {
      Hello: function () {
          return StrJSToStrCS('HELLO WORLD!');
      },
  
      ConsoleLog: function (str) {
          console.log(StrCSToStrJS(str));
      }
  };
  
  mergeInto(LibraryManager.library, lib);
  

• To define these functions in .jspre file after reading this

  the .jspre files are added to the build using the --pre-js option, while the .jslib are added using the --js-library option

  .jspre file:

  function StrJSToStrCS (str) {
      const bufferSize = lengthBytesUTF8(str) + 1;
      const buffer = _malloc(bufferSize);
      stringToUTF8(str, buffer, bufferSize);
      return buffer;
  }
  
  function StrCSToStrJS (str) {
      return UTF8ToString(str);
  }
  

  .jslib file:

  const lib = {
      Hello: function () {
          return StrJSToStrCS('HELLO WORLD!');
      },
  
      ConsoleLog: function (str) {
          console.log(StrCSToStrJS(str));
      }
  };
  
  mergeInto(LibraryManager.library, lib);
  

• To simply define these functions as methods in the same object:

  const lib = {
      StrJSToStrCS: function(str) {
          const bufferSize = lengthBytesUTF8(str) + 1;
          const buffer = _malloc(bufferSize);
          stringToUTF8(str, buffer, bufferSize);
          return buffer;
      },
  
      StrCSToStrJS: function(str) {
          return UTF8ToString(str);
      },
  
      Hello: function() {
          return this.StrJSToStrCS('HELLO WORLD!');
      },
  
      ConsoleLog: function(str) {
          console.log(this.StrCSToStrJS(str));
      }
  }
  
  mergeInto(LibraryManager.library, lib);
  

But whatever I do, he writes every time in console that StrJSToStrCS/StrCSToStrJS is not defined

I don't understand at all why the last method doesn't work. Isn't lib just a simple object?

Is it possible to make these two functions global for all .jslib files?