Built-in help

Red has an exceptional built-in help. There is a large amount of information you can get about the language and about your own code just typing a few commands on the console.

function! ? (or help)        Red-by-example                

Gives information about all of Red's reserved words and also about your own code. You may also type help, but ? is, of course, shorter. ? by itself prints information about how to use help.

>> ? now




    Returns date and time.

    NOW is a native! value.


    /year        => Returns year only.

    /month       => Returns month only.

    /day         => Returns day of the month only.

    /time        => Returns time only.

    /zone        => Returns time zone offset from UCT (GMT) only.

    /date        => Returns date only.

    /weekday     => Returns day of the week as integer (Monday is day 1).

    /yearday     => Returns day of the year (Julian).

    /precise     => High precision time.

    /utc         => Universal time (no zone).


    [date! time! integer!]

>> a: [1 2 3]
== [1 2 3]

>> help a
A is a block! value: [1 2 3]

>> help block!    
       a                length: 3  [1 2 3]
   cancel-captions  length: 3  ["cancel" "delete" "remove"]

>> a: function [a b] [a + b]
== func [a b][a + b]

>> ? a
       A a b
       A is a function! value.

You can get information about complex objects:

If you don't know exactly what you are looking for, "?" will perform a search for you:

>> ? -to

    hex-to-rgb      function!     Converts a color in hex format to a tuple value; returns NONE if it f...

    link-sub-to-parent function!     [face [object!] type [word!] old new /local parent]

    link-tabs-to-parent function!     [face [object!] /init /local faces visible?]

You can find all defined words of a given datatype!

>> ? tuple!

   Red              255.0.0

   white            255.255.255


   black            0.0.0

   gray             128.128.128

    ; ... the list is too long!

function! what        Red-by-example                

Prints a list of globally-defined functions. Try it!

function! source        Red-by-example        

Shows the source code for a mezzanine function or a user created function.

Try source replace .

 mezzanine functions

Red interpreter has:

  • the native functions which are "embedded" in the interpreter and are executed at a very low level;
  • and mezzanine functions which, even though they are part of Red interpreter (come in the Red executable) are created using Red, that is, they have a source code you can read using source.

function! about        Red-by-example        

Display version number and build date.

< Previous topic                                                                                          Next topic >