707661 - [ASC BUG] Must allow the use of "undefined" in more contexts

Status: VERIFIED FIXED

(Tamarin Graveyard :: Tools, defect, P2)

Description

[Lars T Hansen]

The fix for bug #706469 made undefined values visible more generally by constant-expression-evaluating the expression "undefined".  It turns out that undefined is used broadly to generate default values, for comparisons, and so on, even in contexts where it is not very sensible to do so (eg comparing it to Object values), ie, it is used synonymously with null and 0 and false.

In default value and initialization contexts we allow such usage through checkDefaultValue() but in other contexts we use coerce(), which is stricter.  It is not desirable to have two different rules, and it is not desirable to break a bunch of programs.  Hence it is probably the case that coerce() should allow the conversion of undefined values to other types (and ideally ASC should perform such conversions at compile time, of course).

Comment 1

[Lars T Hansen]

changeset:   76:55c204c71b8c
tag:         tip
user:        Lars T Hansen <[e-mail]>
date:        Mon Dec 05 16:37:36 2011 +0100
summary:     Allow undefined to be coerced to all other types in coerce()

Comment 2

[Lars T Hansen]

Reopening; I did test it but there are cases that are not working properly.  Inexplicably we still see an error here:

  function f(o:Object = undefined)
  {
    if (o == undefined)
      print("Ho");
  }

Comment 3

[Lars T Hansen]

changeset:   78:fcbc9c325af9
tag:         tip
user:        Lars T Hansen <[e-mail]>
date:        Tue Dec 06 15:54:36 2011 +0100
summary:     Fix several bugs (unavailable atm due to bugzilla downage), dealing with comparison with undefined and mixed math with float4 as one operand, all in strict mode.

Comment 4

[Brent Baker]

testmedia landed with:
changeset:   7035:9dde02afd510
user:        Lars T Hansen <[e-mail]>
date:        Tue Dec 06 15:56:22 2011 +0100
summary:     Updated asc.jar to 78:fcbc9c325af9, added several asc regression tests in as3/asc.