Gazelle 22 "Left Arrow Script"
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"Left arrow script" is one of Gazelle 22's two scripting languages. It is the powerful one of the two.

-Usually, you write one command per line
-Each command contains at most one action and at most one assignment
-The language is case-sensitive
-You can add comments like in Java with /* */ or //
-You can write multiple commands in one line by separating them with a semicolon
-Arguments to functions are separated by spaces
-You can use integer and string literals like in Java
-You can use true, false and null

It's called "left arrow script" because the left arrow (variable assignment) is its only actual operator (not counting ; and {}).


Operations
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You can call any global function defined in Gazelle. Example:

  infoBox "hello"   // show a popup with the text "hello"
  
You can assign the result of a function call to a variable:

  time <- tsNow     // get current time as a Timestamp object
  infoBox time      // show as popup
  
Note that this script requires 2 lines because only one operation is allowed per command.
  
Variables can be overwritten and don't have to be declared.


Creating objects
----------------

You can create an instance of any Java class and call methods on the object:

  list <- new ArrayList
  list add "hello"
  list add "world"
  infoBox list       // shows [hello, world]
  
(Currently you can also say "list <- ArrayList", but this is ambiguous and may be removed in a future version.)
  
You can pass parameters to the constructor:

  pair <- new Pair "hello" "world"
  infoBox pair      // shows <hello, world>
  

Java operators (+, * etc)
-------------------------
  
Java operators can't be used directly but we have functions that do the same thing (if we don't, we'll add them):

  x <- plus 1 2
  infoBox x


Function definitions
--------------------

You can define functions in your script, with arguments. The function can return a value (which is the result of the last command in the function).

  def doubleMe x { mul x 2 }

  x <- doubleMe 5
  infoBox x        // shows 10