Expand description
§TyLisp: a domain-specific language for type-system calculations
This crate is still experimental and likely to undergo significant changes. It is developed primarily to support the needs of
memquery.
tylisp is a programming language embedded in Rust’s macro and
type systems.
Its main purpose is to ease the burden of writing extremely-generic
Rust code that comes from a proliferation of trait bounds.
Because tylisp calculations occur entirely within the type system,
any object that the used operations support will automatically be
accepted.
tylisp has two distinct operating modes:
Evalmode will calculate a type, but doesn’t provide any means to produce a value of that type. It’s mostly used to convey extra context informtion that can help select one of several implementations.Calcadditionally provides a mechanism to apply the same actions to runtime values, which will produce a result value of the specified type. This allows us to define overloaded functions that have a return type dependent on argument types.
§Semver Hazards
Writing code this way poses unique challenges to versioning.
All of the Rust functions defined via tylisp expose their internal
algorithm in the public API.
Thus, any change to the internal workings of a function have the
potential to break downstream code.
Best practice is to specify traditional trait bounds that constrain
the input and output types, and manually verify that the tylisp
code always satisfies these constraints.
Re-exports§
pub use typenum;
Modules§
- engine
- macros
- marker_
traits - Marker traits to ease integration with traditional Rust code
- ops
Macros§
- calc
- calc_
bound - calc_ty
- defmacro
- Setup a new macro function, and some match arms for implementation
- defun
- Setup a new function, and some match arms for implementation
- defun_
nocalc - defun_
rust - eval
- Shorthand for resolving a lisp expression into its resultant type
- literal
- Define types as lisp literals, which evaluate to themselves
- non_
calc_ literal - partial
- sexpr
- sexprs, the building blocks of everything Lisp
- sexpr_
pat - Build an sexpr type from expressions.
- sexpr_
pat_ ty - Build an sexpr type from expressions.
- sexpr_
quoted_ types - sexpr_
quoted_ vals - Internal macro to extract quoted expressions from an
sexpr - sexpr_
val - Build an sexpr type from expressions.
- uuid_
new_ v4 - Construct a new random UUID