This commit introduces several improvements:
- Pre-compiles regular expressions in `ast/tester.rs` to avoid redundant
compilation, improving performance.
- Replaces `.extension().map_or(false, |ext| ext == "myc")` with the
more concise and readable `.extension().is_some_and(|ext| ext ==
"myc")`.
- Simplifies upvalue capture logic by using `.or_default()` instead of
`.or_insert_with(HashSet::new)`.
- Adds a `Default` implementation for `TracingObserver`.
- Optimizes string literal parsing in `highlight_myc` to correctly
handle escape sequences.
- Uses `saturating_sub` for bracket depth to prevent underflow.
The `UpvalueAnalyzer` now correctly identifies which lambdas capture
which variable declarations, rather than just marking declarations that
need boxing. This information is stored in a `capture_map`.
The `Binder` has been updated to use this new `capture_map` instead of a
`HashSet` of boxed declarations. The `DefLocal` node in `bound_nodes.rs`
now stores a `captured_by` field, which is a list of lambda identities
that capture the local variable.
A new `dumper` module has been added to provide a human-readable
representation of the bound AST, including information about captured
variables.
The `VM` has been updated to use the `captured_by` field to determine if
a local variable needs to be stored in a `Cell`, rather than relying on
a boolean `is_boxed` flag.
An example script `extreme_capture.myc` has been added to test deep
nesting and variable capture.
A new "Dump AST" button has been added to the UI, which uses the new
`Dumper` to display the bound AST.
The binder now uses an `UpvalueAnalyzer` to identify local variables
that are captured by nested functions. These identified variables are
marked with `is_boxed: true` during `DefLocal` node creation. The VM
then uses this flag to wrap such variables in a `Value::Cell` (using
`Rc<RefCell<_>>`) to ensure they can be mutated across function calls.
feat: Introduce boxing for captured variables
Add UpvalueAnalyzer to identify variables captured by nested lambdas.
Modify Binder to use the analyzer and mark captured local variables for
boxing.
Update BoundKind::DefLocal to include an `is_boxed` flag.
Update VM to box captured variables when they are defined.
Add tests for upvalue capture detection.
Michael Schimmel