This PR changes all `lean-toolchain` to use relative toolchain paths
instead of `lean4` and `lean4-stage0` identifiers, which removes the
need for manually linking toolchains via Elan.
After this PR, at least Elan 4.2.0 and 0.0.224 of the Lean VS Code
extension will be needed to edit core.
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
This PR prevents symbol clashes between (non-`@[export]`) definitions
from different Lean packages.
Previously, if two modules define a function with the same name and were
transitively imported (even privately) by some downstream module,
linking would fail due to a symbol clash. Similarly, if a user defined a
symbol with the same name as one in the `Lean` library, Lean would use
the core symbol even if one did not import `Lean`.
This is solved by changing Lean's name mangling algorithm to include an
optional package identifier. This identifier is provided by Lake via
`--setup` when building a module. This information is weaved through the
elaborator, interpreter, and compiler via a persistent environment
extension that associates modules with their package identifier.
With a package identifier, standard symbols have the form
`lp_<pkg-id>_<mangled-def>`. Without one, the old scheme is used (i.e.,
`l_<mangled-def>`). Module initializers are also prefixed with package
identifier (if any). For example, the initializer for a module `Foo` in
a package `test` is now `initialize_test_Foo` (instead of
`initialize_Foo`). Lake's default for native library names has also been
adjusted accordingly, so that libraries can still, by default, be used
as plugins. Thus, the default library name of the `lean_lib Foo` in
`package test` will now be `libtest_Foo`.
When using Lake to build the Lean core (i.e., `bootstrap = true`), no
package identifier will be used. Thus, definitions in user packages can
never have symbol clashes with core.
Closes#222.
This PR strips `lib` prefixes and `_shared` suffixes from plugin names.
It also moves most of the dynlib processing code to Lean to make such
preprocessing more standard.
This PR adds `Lean.loadPlugin` which exposes functionality similar to
the `lean` executable's `--plugin` option to Lean code.
This will allow custom Lean frontends (e.g., Lake, the Lean language
server) to also load plugins.
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Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>
