; A SAL program consists of comments and expressions.  Comments start
; with a semi-colon last until the end of the line. You are reading a
; comment block.  An expression is anything that you execute to
; accomplish a task. To execute an expression put your cursor just
; after the end of its text and press COMMAND-Enter. On the Mac the
; COMMAND key is the APPLE key, on Windows and Linux it's the CONTROL
; key. Look in the Console window to see the results of executing the
; command. Do it:

print("Hello, world!")

; Many expressions involve math. In math expressions operators MUST be
; delimited by spaces. If you don't use parentheses then normal
; operator precedence applies:

1 + 2 * 3

; You can use parentheses to group and nest terms as you like:

((1 + 2) * 3)

; Command and function arguments are separated by commas. Execute this
; command several times to see what it does:

print("my key number: ", between(60, 90))

; You can read help about commands and functions by placing your
; cursor on the word you want to look up and pressing COMMAND-D. Try
; this on the symbols 'print' and 'between' in the previous example.

; Errors: when you execute somethin that contains a mistake you will
; see an error message printed in the Console window. Sometimes this
; message is helpful, sometimes its not so useful. Such is life.  Many
; mistakes involve syntax errors or undefined terms as shown in these
; two examples:

(1 + 2 * 3

foo

; Expressions can become quite complex and often span more than one
; line.  Here is an example of a moderately complex command. To
; execute it, place your cursor just after the word 'end' and press
; COMMAND-Enter several times to see what it does:

begin
  with root = between(60, 90),
       third = root + pick(3,4) ,
       fifth = root + 7
  print("My random chord: ", note( list( root, third, fifth)))
end

; many expressions you write in this course will make sound!  Here is
; a version of the preceding algorithm that sends the note data out
; the midi port.  Press COMMAND-Enter several times to hear what it
; does:

begin
  with root = between(60, 90),
       third = root + pick(3,4) ,
       fifth = root + 7
  send("mp:midi", key: root)
  send("mp:midi", key: third)
  send("mp:midi", key: fifth)
end