Inverted syntax with conditional expressions

In traditional syntax conditional expressions are usually shown before the action within a statement or code block:

 IF raining=true THEN needumbrella=true 
In inverted syntax, the action is listed before the conditional expression in the statement or code block:

 needumbrella=true IF raining=true 
Inverted syntax with assignment

In traditional syntax, assignments are usually expressed with the variable appearing before the expression:

 a = 6
In inverted syntax, the expression appears before the variable:

 6 = a
Task

The task is to demonstrate support for inverted syntax forms within the language by showing both the traditional and inverted forms.

  6 -> a : Push 6 on the stack and set the top of the stack as value of local variable a (top of the stack is consumed)
  6 := a : Push 6 on the stack and set the top of the satck as value of  attribute a (top of the stack is consumed).
  raining ifTrue: [ true ->needumbrella ]
