Associative Array library that mirrors druntime, but is fully templated
To use this package, run the following command in your project's root directory:
Put the following dependency into your project's dependences section:
Library version of druntime AA
This library is a template-library version of the AA implementation used by the d programming language. It is binary compatbile, so reinterpret-casting a
Hash!(K, V) to/from a
V[K] is valid.
If any changes are made to the druntime AA implementation, this library may stop being binary compatible (or will be tied to specific versions). The latest D version tested with this library is 2.099.1
- Special mechanisms are not possible with library code. For instance, the outer hash of nested hashes knowing that it is being used for an assignment operation.
- For now, only
opIndexAssignis defined for adding a value to a
Hash. This means things like
hash[unassignedKey]++will not work.
- Not all "methods" of AAs are implemented yet, e.g.
require. These will be added.
- You can build a
Hash!(K, V)at compile time, and at runtime use it as a
Compatibility/conversion to language AA
The code is built to use the same exact layout and hash implementation as the builtin language AA. There is a difference in that
Hash uses compile-time information about the types to compute hashes, and uses the language to properly manage lifetimes. The druntime AA implementation is all based on
TypeInfo, and therefore must handle all these mechanisms manually.
In particular, the AA builds a fake
TypeInfo for the
Entry struct that contains a key and value (a thing that has no formal type). Because it is using compile-time introspection, a
Hash does not use the
TypeInfo for this information, and therefore doesn't need it.
However, when converting to an AA, it ensures the
TypeInfo is properly populated, but instead of using a fake
TypeInfo, the actual
TypeInfo for the
Entry struct is used. This should be binary compatible with the AA, because the AA's fake is attempting to construct a fake
TypeInfo that would mimic what a real
TypeInfo would be.
asAA UFCS method to extract an associative array from a given hash.
You can just assign a
Hash from a compatible AA. By compatible, I mean that the AA's keys convert to the
Hash's keys, and the AA's values convert to the
Hash's values. If the keys and values are the same type, the
Hash will use the AA's internal representation directly.
Tests are sparse at this time. Just enough to ensure the binary compatibility is working, and that the hash works as expected. I plan to add more.
- Try and ensure all methods/properties are identical to builtin AAs
- Improve tests
- flesh out
@safeand other attributes, make sure they are inferred correctly.
- Investigate ways to prove the layout/code of the builtin AA has not changed (even if done via CI).
- Registered by Steven Schveighoffer
- 0.0.1 released a year ago
- Copyright © 2022, Steven Schveighoffer, Digital Mars