In the process of implementing a new computer language, the

point at which the language is sufficiently effective that one

can implement the language in itself. That is, for a new

language called, hypothetically, FOOGOL, one has reached

break-even when one can write a demonstration compiler for

FOOGOL in FOOGOL, discard the original implementation

language, and thereafter use working versions of FOOGOL to

develop newer ones. This is an important milestone. See MyFavourite Toy Language.