This PR fixes name mangling to be unambiguous / injective by adding `00`
for disambiguation where necessary. Additionally, the inverse function,
`Lean.Name.unmangle` has been added which can be used to unmangle a
mangled identifier. This unmangler has been added to demonstrate the
injectivity but also to allow unmangling identifiers e.g. for debugging
purposes.
Closes#10724
This PR introduces a `coinductive` keyword, that can be used to define
coinductive predicates via a syntax identical to the one for `inductive`
keyword. The machinery relies on the implementation of elaboration of
inductive types and extracts an endomap on the appropriate space of the
predicates from the definition that is then fed to the
`PartialFixpoint`. Upon elaborating definitions, all the constructors
are declared through automatically generated lemmas.
For example, infinite sequence of transitions in a relation, can be
given by the following:
```lean4
section
variable (α : Type)
coinductive infSeq (r : α → α → Prop) : α → Prop where
| step : r a b → infSeq r b → infSeq r a
/--
info: infSeq.coinduct (α : Type) (r : α → α → Prop) (pred : α → Prop) (hyp : ∀ (x : α), pred x → ∃ b, r x b ∧ pred b)
(x✝ : α) : pred x✝ → infSeq α r x✝
-/
#guard_msgs in
#check infSeq.coinduct
/--
info: infSeq.step (α : Type) (r : α → α → Prop) {a b : α} : r a b → infSeq α r b → infSeq α r a
-/
#guard_msgs in
#check infSeq.step
end
```
The machinery also supports `mutual` blocks, as well as mixing inductive
and coinductive predicate definitions:
```lean4
mutual
coinductive tick : Prop where
| mk : ¬tock → tick
inductive tock : Prop where
| mk : ¬tick → tock
end
/--
info: tick.mutual_induct (pred_1 pred_2 : Prop) (hyp_1 : pred_1 → pred_2 → False) (hyp_2 : (pred_1 → False) → pred_2) :
(pred_1 → tick) ∧ (tock → pred_2)
-/
#guard_msgs in
#check tick.mutual_induct
```
---------
Co-authored-by: Joachim Breitner <mail@joachim-breitner.de>
This PR adds support for plugins to Lake. Precompiled modules are now
loaded as plugins rather than via `--load-dynlib`.
Additional plugins can be added through an experimental `plugins`
configuration option. The syntax for specifying this is not yet
convenient, and will be improved in future changes. A parallel `dynlibs`
configuration option has been added for specifying additional dynamic
libraries to build and pass to `--load-dynlib`.
This PR also changes the default directory for `.olean`, `.ilean`, and
module dynamic libraries (i.e., `leanLibDir`) to `lib/lean` instead of
the previous default of `lib`. This avoids potential name clashes
between single module shared libraries and the shared libraries of a
full `lean_lib`.
On non-Windows systems, module dynamic libraries are no longer linked to
their imports or external symbols. Symbols from those libraries are left
unresolved until load time. This avoids nesting these dependencies
within the shared library and means Lake no longer needs to augment the
shared library path to allow Lean to resolve such nested dependencies on
load.
