Added explicit assertions for debugging

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Readded replaceWithIndependentCopyForInlining because we need to have a BlockNodeWithContext here, otherwise it will be a normal block node

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Added column and line number to block method names

- can't use usual colon here, because it would be counted as a parameter *sigh*

Signed-off-by: Stefan Marr <git@stefan-marr.de>