d4468affb7
AstGen result locations now have a `coerced_ty` tag which is the same as `ty` except it assumes that Sema will do a coercion, so it does not redundantly add an `as` instruction into the ZIR code. This results in cleaner ZIR and about a 14% reduction of ZIR bytes. param and param_comptime ZIR instructions now have a block body for their type expressions. This allows Sema to skip evaluation of the block in the case that the parameter is comptime-provided. It also allows a new mechanism to function: when evaluating type expressions of generic functions, if it would depend on another parameter, it returns `error.GenericPoison` which bubbles up and then is caught by the param/param_comptime instruction and then handled. This allows parameters to be evaluated independently so that the type info for functions which have comptime or anytype parameters will still have types populated for parameters that do not depend on values of previous parameters (because evaluation of their param blocks will return successfully instead of `error.GenericPoison`). It also makes iteration over the block that contains function parameters slightly more efficient since it now only contains the param instructions. Finally, it fixes the case where a generic function type expression contains a function prototype. Formerly, this situation would cause shared state to clobber each other; now it is in a proper tree structure so that can't happen. This fix also required adding a field to Sema `comptime_args_fn_inst` to make sure that the `comptime_args` field passed into Sema is applied to the correct `func` instruction. Source location for `node_offset_asm_ret_ty` is fixed; it was pointing at the asm output name rather than the return type as intended. Generic function instantiation is fixed, notably with respect to parameter type expressions that depend on previous parameters, and with respect to types which must be always comptime-known. This involves passing all the comptime arguments at a callsite of a generic function, and allowing the generic function semantic analysis to coerce the values to the proper types (since it has access to the evaluated parameter type expressions) and then decide based on the type whether the parameter is runtime known or not. In the case of explicitly marked `comptime` parameters, there is a check at the semantic analysis of the `call` instruction. Semantic analysis of `call` instructions does type coercion on the arguments, which is needed both for generic functions and to make up for using `coerced_ty` result locations (mentioned above). Tasks left in this branch: * Implement the memoization table. * Add test coverage. * Improve error reporting and source locations for compile errors.
A general-purpose programming language and toolchain for maintaining robust, optimal, and reusable software.
Resources
- Introduction
- Download & Documentation
- Chapter 0 - Getting Started | ZigLearn.org
- Community
- Contributing
- Code of Conduct
- Frequently Asked Questions
- Community Projects
Installation
- download a pre-built binary
- install from a package manager
- build from source
- bootstrap zig for any target
License
The ultimate goal of the Zig project is to serve users. As a first-order effect, this means users of the compiler, helping programmers to write better software. Even more important, however, are the end-users.
Zig is intended to be used to help end-users accomplish their goals. Zig should be used to empower end-users, never to exploit them financially, or to limit their freedom to interact with hardware or software in any way.
However, such problems are best solved with social norms, not with software licenses. Any attempt to complicate the software license of Zig would risk compromising the value Zig provides.
Therefore, Zig is available under the MIT (Expat) License, and comes with a humble request: use it to make software better serve the needs of end-users.
This project redistributes code from other projects, some of which have other licenses besides MIT. Such licenses are generally similar to the MIT license for practical purposes. See the subdirectories and files inside lib/ for more details.