Tyl system functions features:

• All system function names are reserved, and cannot be used as a variable or function name
• A system function is used as a regular function
• A system function will not be activated if it does not have the right parameters

Throughout this guide all system functions in code boxes are in dark blue color.

We met the print system function in get started page. print function is used to print messages to the run box. print function has only one parameter, and that is object parameter.

Here's print function description:

object parameter is self explanatory but nonetheless can be detailed as:

Any function has a return value. For regular functions, it is the value of their last executed statement, but system functions has their own inherent return value. System function return value will be written in the function description after the parameters, prepended by the arrow symbol '→'.

Here's print description with return value:

object return value, will be detailed as:



Note that if the return value is one of the function parameters, it may not be detailed, and the return value will be the value of the parameter after the function has finished to be executed.

Here's full len system function description:

Some system function parameters are optional, meaning, the function do not require them. For ex., the beep system function has two parameters, but optionally can be called without parameters. Another example is string.section function in string module that its length parameter can be omitted. So if a parmeter has default value or the description specifies that it can be omitted, than this is an optional parameter.

All system functions are in System Functions Reference