We're still missing predicates (need to be able to call functions for that
one) and assignments into dictionaries. But we now can deconstruct a list
and check against constants.
So things like this work now:
[1 foo ~bar [a b]] = [1 "Hello" 2 3 4 [5 6]]
# foo is: "Hello"
# bar is: [2 3 4]
# a is: 5
# b is: 6
Pretty cool :)
If you assign into a member access (`foo.bar = baz` or `foo@bar = baz`), it
is no longer permitted that the LHS of the at/dot is an arbitrary
assignable. It now must be a variable, at or dot. This disallows some silly
constructs (e.g. `[foo]@bar = baz`), increases the similarity to function
parameters and should make writing the evaluation code for these more easy.
The previous representation didn't properly model the fact that an
assignable / parameter can only be expanded, if it's a list element. This
now better models this. Other than being more correct, this should also
make evaluating these a bit easier.
While I was at it, I also improved the error message for multiple
expansions on the same level and added tests for these.
Since we're using refcounts, we don't really copy anything and no error can
occur. So let's make these callbacks return void to simplify things. This
also makes the return value false of the value getters unambiguous: It now
always means that the key was not present.
This is analogous to dictionaries and ensures that no circular references
can be created when using the exported API in apfl.h.
This also changes apfl_value_copy into apfl_value_incref to better reflect
what it does and to reflect that it is no longer an operation that can
fail.
Increasing the refcount (confusingly called copy before, fixed that too)
didn't work properly, as the object was copied and the refcount was only
updated in one of the copies.
This avoids copying the string every time we pass it around. Not too
important right now, but will become important onve we're able to evaluate
more complex expressions.
This replaces the grow_cap function with the ensure_cap family of
functions, as they actually do what you want: You'll likely not want to
blindly increase the capacity of a growable, but you want to make sure that
the capacity is large enough to hold the elements you're about to insert.
It's really easy to accidentally pass an uninitialized string as dst into
the copy function, which will result in an free() call to an arbitrary
pointer. Maybe it's a better idea to not deinit the dst string before
copying? The documentation at least makes it more clear and the new
apfl_string_blank() function makes it easy to create an empty string.
With the varargs approach that was used before, it was very easy to add a
list item of the wrong type, which would (hopefully) result in an assertion
violation, because va_arg() then read some senseless data.
A useful source reader implementation to pass in a source saved as an
in-memory string into the tokenizer.
This replaces the string_src_reader in the tokenizer_test and is even a bit
more flexible, by allowing any aplf_string_view as the source.
- Simplify return types: Many functions that returned
`enum parse_fragment_result` only ever returned PF_OK or PF_ERROR.
Changing these functions to return bool simplifies things a lot. This
also helped in identifying some places where I didn't handle all
parse_fragment_result values properly.
- More cleaning up
- Allow linebreaks inside parenthesis
