Previously, AK::Function would accept _any_ callable type, and try to
call it when called, first with the given set of arguments, then with
zero arguments, and if all of those failed, it would simply not call the
function and **return a value-constructed Out type**.
This lead to many, many, many hard to debug situations when someone
forgot a `const` in their lambda argument types, and many cases of
people taking zero arguments in their lambdas to ignore them.
This commit reworks the Function interface to not include any such
surprising behaviour, if your function instance is not callable with
the declared argument set of the Function, it can simply not be
assigned to that Function instance, end of story.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
This adds an option "Lenient" that makes the reader conform to what
appears to be the norm in spreadsheet-land:
- Treat missing values as empty ones
- Update previously read rows if another row with more columns are seen
afterwards
This broke in 6a6f19a72f, which replaced
the representation of columns with numbers.
As a result, the save logic would store cells as
"\x<column_index><row_number>", which is obviously wrong.
Fixes#5905.
Also simplifies the control flow in `import_worksheet` a bit.
