code: public final CALC function(Class<? extends Function> function, Object... values) {
          Function fn = CacheExtension.getFunction(function);
          FunctionData fd = new FunctionData(fn, values);
          this.infix.addFunction(fd);
  
          return getThis();
      }
docs: Append function with value to expression.
  
  <br/>
  e.g. Abs.class, -5 => abs(-5)
  
  @param function
  @param values can accept any object that {@link Num} can work with
  @return
  @see {@link Function}