roland/xo-alloc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

xo-expression: + Lambda.complete_assembly_from_body()

Browse source
This commit is contained in:
Roland Conybeare 2024-08-22 15:45:31 -04:00
commit b906fdfa5a
2 changed files with 82 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

15
include/xo/expression/Lambda.hpp
View file

@ -106,7 +106,6 @@ namespace xo {
const rp<LocalEnv> & local_env,
const rp<Expression> & body);
protected:
/** compute free-variable set for this lambda **/
std::set<std::string> calc_free_variables() const;
@ -118,6 +117,14 @@ namespace xo {
**/
std::map<std::string, rp<Variable>> regularize_layer_vars();
/** compute derived members
* (type_str_, free_var_set_, captured_var_set_, layer_var_map_,
* nested_lambda_map_)
* once .body_ is established
**/
void complete_assembly_from_body();
protected:
/** lambda name. Initially supporting only form like
* (define (foo x y z)
* (+ (* x x) (* y y) (* z z)))
@ -177,9 +184,9 @@ namespace xo {
const rp<Expression> & body);
static rp<LambdaAccess> make_empty();
/* TODO: make sure Lambda members that depend on non-emtpy body
* get calc'd
*/
/** assign body + compute derived members
* (see complete_assembly_from_body())
**/
void assign_body(const rp<Expression> & body);
private:

72
src/expression/Lambda.cpp
View file

@ -154,6 +154,68 @@ namespace xo {
return var_map;
} /*regularize_layer_vars*/
void
Lambda::complete_assembly_from_body() {
if (body_) {
TypeDescr lambda_td
= assemble_lambda_td(this->local_env_->argv(), body_);
if (lambda_td)
this->type_str_ = assemble_type_str(lambda_td);
this->layer_var_map_ = this->regularize_layer_vars();
this->free_var_set_ = this->calc_free_variables();
std::map<std::string, ref::brw<Lambda>> nested_lambda_map;
{
this->body_->visit_layer
([&nested_lambda_map]
(ref::brw<Expression> expr)
{
if (expr->extype() == exprtype::lambda) {
ref::brw<Lambda> lm = Lambda::from(expr);
nested_lambda_map[lm->name()] = lm.get();
}
});
}
this->nested_lambda_map_ = std::move(nested_lambda_map);
/* establish the set of captured local vars.
* These are any formal parameters that appear free in
* any layer of a nested lambda.
*/
std::set<std::string> captured_var_set;
{
for (const auto & ix : nested_lambda_map_) {
std::set<std::string> nested_free_var_set
= ix.second->get_free_variables();
for (const auto & jx : nested_free_var_set) {
/* check whether variable *jx is one of this lambda's
* formals
*/
auto bind = this->local_env_->lookup_local_binding(jx);
if (bind.i_link_ == 0) {
/* yup, it's a formal parameter of this lambda */
captured_var_set.insert(jx);
}
}
}
}
this->captured_var_set_ = std::move(captured_var_set);
/* in particular:
* - establish binding path (intrusively) for each variable
* assigns Variable::path_
*/
this->body_->attach_envs(local_env_);
}
}
Lambda::Lambda(const std::string & name,
TypeDescr lambda_td,
const rp<LocalEnv> & local_env,
@ -209,7 +271,9 @@ namespace xo {
= ix.second->get_free_variables();
for (const auto & jx : nested_free_var_set) {
/* check whether variable *jx is one of this lambda's formals */
/* check whether variable *jx is one of this lambda's
* formals
*/
auto bind = this->local_env_->lookup_local_binding(jx);
if (bind.i_link_ == 0) {
@ -284,6 +348,12 @@ namespace xo {
: Lambda(name, lambda_td, local_env, body)
{}
void
LambdaAccess::assign_body(const rp<Expression> & body) {
this->body_ = body;
this->complete_assembly_from_body();
}
} /*namespace ast*/
} /*namespace xo*/