When I titled the article around
Allan Gregersen's Javeleon "Update Space Invaders Game While
Playing It", I was being slightly frivolous. The point of Javeleon
isn't to update a space invaders game while playing it, of course.
Instead, the point is, more generically, to reload features while
keeping their state.
But, in the comments to that article, Antonio Vieiro and
Dominique De Vito pointed to their 'need' for such games being made
available (Antonio because he'd like to...