110 lines
3.2 KiB
C++
110 lines
3.2 KiB
C++
/* file ConvertExpr.hpp
|
|
*
|
|
* author: Roland Conybeare, Aug 2024
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "Expression.hpp"
|
|
|
|
namespace xo {
|
|
namespace scm {
|
|
/** @class Convertexpr
|
|
* @brief Convenience for automatic type conversion
|
|
*
|
|
* This is equivalent to calling a built-in primitive
|
|
* that performs the conversion.
|
|
*
|
|
* We rely on this for convenience, for example to parse
|
|
* code like
|
|
*
|
|
* def foo : i16 = 0
|
|
**/
|
|
class ConvertExpr : public Expression {
|
|
public:
|
|
static rp<ConvertExpr> make(TypeDescr dest_type,
|
|
rp<Expression> arg);
|
|
|
|
static bp<ConvertExpr> from(bp<Expression> x) {
|
|
return bp<ConvertExpr>::from(x);
|
|
}
|
|
|
|
const rp<Expression> & arg() const { return arg_; }
|
|
|
|
// ----- Expression -----
|
|
|
|
virtual std::set<std::string> get_free_variables() const override;
|
|
|
|
virtual std::size_t visit_preorder(VisitFn visitor_fn) override {
|
|
std::size_t n = 1;
|
|
|
|
visitor_fn(this);
|
|
|
|
n += arg_->visit_preorder(visitor_fn);
|
|
|
|
return n;
|
|
}
|
|
|
|
virtual std::size_t visit_layer(VisitFn visitor_fn) override {
|
|
std::size_t n = 1;
|
|
|
|
visitor_fn(this);
|
|
|
|
n += this->arg_->visit_layer(visitor_fn);
|
|
|
|
return n;
|
|
}
|
|
|
|
virtual rp<Expression> xform_layer(TransformFn xform_fn) override {
|
|
this->arg_ = this->arg_->xform_layer(xform_fn);
|
|
|
|
return xform_fn(this);
|
|
}
|
|
|
|
virtual void attach_envs(bp<SymbolTable> p) override {
|
|
arg_->attach_envs(p);
|
|
}
|
|
|
|
virtual void display(std::ostream & os) const override;
|
|
virtual std::uint32_t pretty_print(const ppindentinfo & ppii) const override;
|
|
|
|
protected:
|
|
ConvertExpr(TypeDescr dest_type,
|
|
rp<Expression> arg)
|
|
: Expression(exprtype::convert, dest_type),
|
|
arg_{std::move(arg)}
|
|
{}
|
|
|
|
protected:
|
|
/** source expression. Convert
|
|
* @c arg_->valuetype() to @c dest_type_
|
|
**/
|
|
rp<Expression> arg_;
|
|
};
|
|
|
|
/** @class ConvertExprAccess
|
|
* @brief ConvertExpr with writeable members.
|
|
*
|
|
* Convenient when scaffolding a parser,
|
|
* e.g. see xo-parser
|
|
**/
|
|
class ConvertExprAccess : public ConvertExpr {
|
|
public:
|
|
static rp<ConvertExprAccess> make(TypeDescr dest_type,
|
|
rp<Expression> arg);
|
|
static rp<ConvertExprAccess> make_empty();
|
|
|
|
void assign_arg(rp<Expression> arg) { this->arg_ = std::move(arg); }
|
|
|
|
private:
|
|
ConvertExprAccess(TypeDescr dest_type,
|
|
rp<Expression> arg)
|
|
: ConvertExpr(dest_type,
|
|
std::move(arg))
|
|
{}
|
|
};
|
|
} /*namespace scm*/
|
|
} /*namespace xo*/
|
|
|
|
|
|
/* end ConvertExpr.hpp */
|