[tormeh]

Principal component analysis and then ignoring the least important components is the only compression technique I know. Hope it helps.

[sampo]

Well that is a lossy compression, can work nicely to some data (e.g. images), but totally irrelevant in the context of source code compression.

[vardump]

Lossy compression might be just fine for source code, as long as the lossy part is still functionally equivalent.

Think 1000.0 vs 1E3, printf("foo") vs puts("foo"), etc.

[mistercow]

And in fact, RegPack is lossy compression (as are all minifiers). The transformation is totally irreversible.

[tormeh]

Well, he didn't say he only wanted non-lossy compression or that he was working on source code compression.