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#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "resolve_symbols_visitor.h"
#include "errors.h"
#include <iostream>
namespace foundry {
namespace parse {
void resolve_symbols_visitor::visit(group &g)
{
for(auto &i : g.components)
{
current_context = &i;
descend(i);
}
}
void resolve_symbols_visitor::visit(regex &) { }
void resolve_symbols_visitor::visit(string_literal &) { }
void resolve_symbols_visitor::visit(unresolved_symbol &s)
{
auto ntref = nonterminals.find(s.name);
if(ntref != nonterminals.end())
{
*current_context = ntref->second;
if(verbose)
std::cerr << "Immediately resolved nonterminal " << s.name << std::endl;
}
else
{
unresolved_references[s.name].push_back(current_context);
if(verbose)
std::cerr << "Queuing unresolved symbol " << s.name << std::endl;
}
}
void resolve_symbols_visitor::visit(terminal &) { }
void resolve_symbols_visitor::visit(nonterminal &) { }
void resolve_symbols_visitor::visit(root &r)
{
descend(r.rules);
if(verbose)
{
auto n = unresolved_references.size();
if(n)
{
std::cerr << n << " unresolved symbols remaining." << std::endl;
for(auto i : unresolved_references)
{
std::cerr << "Symbol " << i.first << ": " << i.second.size() << " references" << std::endl;
}
throw unknown_production();
}
}
}
void resolve_symbols_visitor::visit(rule &r)
{
nonterminal_ptr nt = new nonterminal;
nt->name = r.name;
nt->rule = &r;
if(verbose)
std::cerr << "Found rule " << r.name << std::endl;
auto ntref = nonterminals.find(r.name);
if(ntref != nonterminals.end())
throw duplicate_rule(r.name);
nonterminals[r.name] = nt;
auto urref = unresolved_references.find(r.name);
if(urref != unresolved_references.end())
{
if(verbose)
std::cerr << "Resolving " << urref->second.size() << " queued references." << std::endl;
for(auto &i : urref->second)
*i = nt;
unresolved_references.erase(urref);
}
descend(r.alternatives);
}
void resolve_symbols_visitor::visit(alternative &a)
{
descend(a.group);
}
}
}
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