#at
compiles:
function A() {
  @x = 3
}
to:
function A() {
  this.x = 3
}
compiles:
run(@)
to:
run(this)

compiles:
@@
to:
this.constructor

compiles:
@@name
to:
this.constructor.name

compiles:
@[k]

to:
this[k]

compiles:
@(x)

to:
this(x)

