C

K&R style.

Headers

0. Prefix header guard symbols with _LIBSAPLING_{file path}_H_.

The static modifier should be on a line by itself above the function signature.
Put parameter casts at the beginning of the function and leave an empty line between them and the rest of the code.
Do not prepend the const modifier to scalar parameters that are passed by value if it is not necessary to do so.
Avoid declaring const pointers if they are a copy anyway (e.g. if they are function parameters but not if they are unique)
When similar functions only differ in some extra parameters put those as the last parameters, keeping the common parameters first and in the same order.
- One exception to this rule is the quantifier parameter in data management implementations, which should always be the first parameter, but some applications only allow one of them.

Sort constructs by:
- Dependency (i.e. if a construct depends on another, the latter should be above it)
- If the construct does not depend on other constructs in the same file then use this order:
  - (1) Constructs that you feel may be implemented outside the file in the future
  - (2) Construct whose implementation is trivial/simpler/shorter
Group together constructs that have a linear dependency path, separating them from the rest of constructs by wrapping them in two empty lines befor and after (i.e. a function that uses pseudo-lambdas that are only used by it would be a group started by two empty lines, a struct, empty line, a predicate function, empty line, an apply function, empty line, the function itself, then finally two empty lines).