title: How to join variable-length parameters as a string
body: <p>I want to pass variable-length parameters in the function, concatenate these parameters with commas, and finally return the form of the string with parentheses. If the parameter type is a string or char *, then automatically With single quotes, how does this work? Thank you!
  For example: join (1, 2, "hello", 3, "world") returns the string "(1, 2, \"hello\", 3, \"world\")"</p>