ChaiScript/chaiscript/chaiscript_eval.hpp

492 lines
20 KiB
C++

// This file is distributed under the BSD License.
// See LICENSE.TXT for details.
#ifndef CHAISCRIPT_EVAL_HPP_
#define CHAISCRIPT_EVAL_HPP_
#include <map>
namespace chaiscript
{
struct ParserError {
std::string reason;
langkit::TokenPtr location;
ParserError(const std::string &why, const langkit::TokenPtr where) : reason(why), location(where){ }
};
struct EvalError : public std::runtime_error {
std::string reason;
langkit::TokenPtr location;
EvalError(const std::string &why, const langkit::TokenPtr where)
: std::runtime_error("Eval error: \"" + why + "\" in '"
+ where->filename + "' line: " + boost::lexical_cast<std::string>(where->start.line+1)),
reason(why), location(where) { }
virtual ~EvalError() throw() {}
};
struct ReturnValue {
dispatchkit::Boxed_Value retval;
langkit::TokenPtr location;
ReturnValue(const dispatchkit::Boxed_Value &return_value, const langkit::TokenPtr where) : retval(return_value), location(where) { }
};
struct BreakLoop {
langkit::TokenPtr location;
BreakLoop(const langkit::TokenPtr where) : location(where) { }
};
template <typename Eval_System>
const dispatchkit::Boxed_Value eval_function (Eval_System &ss, langkit::TokenPtr node, const std::vector<std::string> &param_names, const std::vector<dispatchkit::Boxed_Value> &vals) {
ss.new_scope();
for (unsigned int i = 0; i < param_names.size(); ++i) {
ss.add_object(param_names[i], vals[i]);
}
dispatchkit::Boxed_Value retval;
try {
retval = eval_token(ss, node);
} catch (const ReturnValue &rv) {
retval = rv.retval;
}
ss.pop_scope();
return retval;
}
template <typename Eval_System>
dispatchkit::Boxed_Value eval_token(Eval_System &ss, langkit::TokenPtr node) {
dispatchkit::Boxed_Value retval;
unsigned int i, j;
switch (node->identifier) {
case (TokenType::Value) :
case (TokenType::File) :
for (i = 0; i < node->children.size(); ++i) {
retval = eval_token(ss, node->children[i]);
}
break;
case (TokenType::Identifier) :
if (node->text == "true") {
retval = dispatchkit::Boxed_Value(true);
}
else if (node->text == "false") {
retval = dispatchkit::Boxed_Value(false);
}
else {
try {
retval = ss.get_object(node->text);
}
catch (std::exception &e) {
throw EvalError("Can not find object: " + node->text, node);
}
}
break;
case (TokenType::Real_Number) :
retval = dispatchkit::Boxed_Value(double(atof(node->text.c_str())));
break;
case (TokenType::Integer) :
retval = dispatchkit::Boxed_Value(atoi(node->text.c_str()));
break;
case (TokenType::Quoted_String) :
retval = dispatchkit::Boxed_Value(node->text);
break;
case (TokenType::Single_Quoted_String) :
retval = dispatchkit::Boxed_Value(node->text);
break;
case (TokenType::Equation) :
retval = eval_token(ss, node->children.back());
if (node->children.size() > 1) {
for (i = node->children.size()-3; ((int)i) >= 0; i -= 2) {
dispatchkit::Param_List_Builder plb;
plb << eval_token(ss, node->children[i]);
plb << retval;
try {
retval = dispatch(ss.get_function(node->children[i+1]->text), plb);
}
catch(std::exception &e){
throw EvalError("Can not find appropriate '" + node->children[i+1]->text + "'", node->children[i+1]);
}
}
}
break;
case (TokenType::Variable_Decl): {
ss.add_object(node->children[0]->text, dispatchkit::Boxed_Value());
retval = ss.get_object(node->children[0]->text);
}
break;
case (TokenType::Factor) :
case (TokenType::Expression) :
case (TokenType::Term) :
case (TokenType::Boolean) :
case (TokenType::Comparison) : {
retval = eval_token(ss, node->children[0]);
if (node->children.size() > 1) {
for (i = 1; i < node->children.size(); i += 2) {
dispatchkit::Param_List_Builder plb;
plb << retval;
plb << eval_token(ss, node->children[i + 1]);
try {
retval = dispatch(ss.get_function(node->children[i]->text), plb);
}
catch(std::exception &e){
throw EvalError("Can not find appropriate '" + node->children[i]->text + "'", node->children[i]);
}
}
}
}
break;
case (TokenType::Array_Call) : {
retval = eval_token(ss, node->children[0]);
for (i = 1; i < node->children.size(); ++i) {
dispatchkit::Param_List_Builder plb;
plb << retval;
plb << eval_token(ss, node->children[i]);
try {
retval = dispatch(ss.get_function("[]"), plb);
}
catch(std::out_of_range &oor) {
throw EvalError("Out of bounds exception", node);
}
catch(std::exception &e){
throw EvalError("Can not find appropriate array lookup '[]'", node->children[i]);
}
}
}
break;
case (TokenType::Negate) : {
retval = eval_token(ss, node->children[1]);
dispatchkit::Param_List_Builder plb;
plb << retval;
plb << dispatchkit::Boxed_Value(-1);
try {
retval = dispatch(ss.get_function("*"), plb);
}
catch(std::exception &e){
throw EvalError("Can not find appropriate negation", node->children[0]);
}
}
break;
case (TokenType::Not) : {
bool cond;
try {
retval = eval_token(ss, node->children[1]);
cond = dispatchkit::boxed_cast<bool &>(retval);
}
catch (std::exception) {
throw EvalError("Boolean not('!') condition not boolean", node->children[0]);
}
retval = dispatchkit::Boxed_Value(!cond);
}
break;
case (TokenType::Prefix) : {
retval = eval_token(ss, node->children[1]);
dispatchkit::Param_List_Builder plb;
plb << retval;
try {
retval = dispatch(ss.get_function(node->children[0]->text), plb);
}
catch(std::exception &e){
throw EvalError("Can not find appropriate prefix", node->children[0]);
}
}
break;
case (TokenType::Array_Init) : {
try {
retval = dispatch(ss.get_function("Vector"), dispatchkit::Param_List_Builder());
for (i = 0; i < node->children.size(); ++i) {
try {
dispatchkit::Boxed_Value tmp = eval_token(ss, node->children[i]);
dispatch(ss.get_function("push_back"), dispatchkit::Param_List_Builder() << retval << tmp);
}
catch (std::exception inner_e) {
throw EvalError("Can not find appropriate 'push_back'", node->children[i]);
}
}
}
catch (std::exception e) {
throw EvalError("Can not find appropriate 'Vector()'", node);
}
}
break;
case (TokenType::Map_Init) : {
try {
retval = dispatch(ss.get_function("Map"), dispatchkit::Param_List_Builder());
for (i = 0; i < node->children.size(); ++i) {
try {
dispatchkit::Boxed_Value key = eval_token(ss, node->children[i]->children[0]);
dispatchkit::Boxed_Value slot = dispatch(ss.get_function("[]"), dispatchkit::Param_List_Builder() << retval << key);
dispatch(ss.get_function("="), dispatchkit::Param_List_Builder() << slot << eval_token(ss, node->children[i]->children[1]));
}
catch (std::exception inner_e) {
throw EvalError("Can not find appropriate '=' for map init", node->children[i]);
}
}
}
catch (std::exception e) {
throw EvalError("Can not find appropriate 'Vector()'", node);
}
}
break;
case (TokenType::Fun_Call) : {
std::vector<std::pair<std::string, dispatchkit::Dispatch_Engine::Function_Map::mapped_type> > fn;
dispatchkit::Dispatch_Engine::Stack prev_stack = ss.get_stack();
dispatchkit::Dispatch_Engine::Stack new_stack;
new_stack.push_back(dispatchkit::Dispatch_Engine::Scope());
dispatchkit::Param_List_Builder plb;
for (i = 1; i < node->children.size(); ++i) {
plb << eval_token(ss, node->children[i]);
}
try {
fn = ss.get_function(node->children[0]->text);
ss.set_stack(new_stack);
retval = dispatch(fn, plb);
ss.set_stack(prev_stack);
}
catch(EvalError &ee) {
ss.set_stack(prev_stack);
throw EvalError(ee.reason, node->children[0]);
}
catch(std::exception &e){
ss.set_stack(prev_stack);
throw EvalError("Engine error: " + std::string(e.what()) + " on '" + node->children[0]->text + "'", node->children[0]);
}
catch(ReturnValue &rv) {
ss.set_stack(prev_stack);
retval = rv.retval;
}
}
break;
case (TokenType::Method_Call) : {
std::vector<std::pair<std::string, dispatchkit::Dispatch_Engine::Function_Map::mapped_type> > fn;
dispatchkit::Dispatch_Engine::Stack prev_stack = ss.get_stack();
dispatchkit::Dispatch_Engine::Stack new_stack;
new_stack.push_back(dispatchkit::Dispatch_Engine::Scope());
retval = eval_token(ss, node->children[0]);
if (node->children.size() > 1) {
for (i = 1; i < node->children.size(); ++i) {
dispatchkit::Param_List_Builder plb;
plb << retval;
for (j = 1; j < node->children[i]->children.size(); ++j) {
plb << eval_token(ss, node->children[i]->children[j]);
}
std::string fun_name;
if (node->children[i]->identifier == TokenType::Fun_Call) {
fun_name = node->children[i]->children[0]->text;
}
else {
fun_name = node->children[i]->text;
}
try {
fn = ss.get_function(fun_name);
ss.set_stack(new_stack);
retval = dispatch(fn, plb);
ss.set_stack(prev_stack);
}
catch(EvalError &ee) {
ss.set_stack(prev_stack);
throw EvalError(ee.reason, node);
}
catch(std::exception &e){
ss.set_stack(prev_stack);
throw EvalError("Can not find appropriate '" + fun_name + "'", node);
}
catch(ReturnValue &rv) {
ss.set_stack(prev_stack);
retval = rv.retval;
}
}
}
}
break;
case(TokenType::If_Block) : {
retval = eval_token(ss, node->children[0]);
bool cond;
try {
cond = dispatchkit::boxed_cast<bool &>(retval);
}
catch (std::exception &e) {
throw EvalError("If condition not boolean", node->children[0]);
}
if (cond) {
retval = eval_token(ss, node->children[1]);
}
else {
if (node->children.size() > 2) {
i = 2;
while ((!cond) && (i < node->children.size())) {
if (node->children[i]->text == "else") {
retval = eval_token(ss, node->children[i+1]);
cond = true;
}
else if (node->children[i]->text == "elseif") {
retval = eval_token(ss, node->children[i+1]);
try {
cond = dispatchkit::boxed_cast<bool &>(retval);
}
catch (std::exception &e) {
throw EvalError("Elseif condition not boolean", node->children[i+1]);
}
if (cond) {
retval = eval_token(ss, node->children[i+2]);
}
}
i = i + 3;
}
}
}
}
break;
case(TokenType::While_Block) : {
retval = eval_token(ss, node->children[0]);
bool cond;
try {
cond = dispatchkit::boxed_cast<bool &>(retval);
}
catch (std::exception) {
throw EvalError("While condition not boolean", node->children[0]);
}
while (cond) {
try {
eval_token(ss, node->children[1]);
retval = eval_token(ss, node->children[0]);
try {
cond = dispatchkit::boxed_cast<bool &>(retval);
}
catch (std::exception) {
throw EvalError("While condition not boolean", node->children[0]);
}
}
catch (BreakLoop &bl) {
cond = false;
}
}
retval = dispatchkit::Boxed_Value();
}
break;
case(TokenType::For_Block) : {
dispatchkit::Boxed_Value condition;
bool cond;
try {
if (node->children.size() == 4) {
eval_token(ss, node->children[0]);
condition = eval_token(ss, node->children[1]);
}
else if (node->children.size() == 3){
condition = eval_token(ss, node->children[0]);
}
cond = dispatchkit::boxed_cast<bool &>(condition);
}
catch (std::exception &e) {
throw EvalError("For condition not boolean", node);
}
while (cond) {
try {
if (node->children.size() == 4) {
eval_token(ss, node->children[3]);
eval_token(ss, node->children[2]);
condition = eval_token(ss, node->children[1]);
}
else if (node->children.size() == 3) {
eval_token(ss, node->children[2]);
eval_token(ss, node->children[1]);
condition = eval_token(ss, node->children[0]);
}
cond = dispatchkit::boxed_cast<bool &>(condition);
}
catch (std::exception &e) {
throw EvalError("For condition not boolean", node);
}
catch (BreakLoop &bl) {
cond = false;
}
}
retval = dispatchkit::Boxed_Value();
}
break;
case (TokenType::Function_Def) : {
unsigned int num_args = node->children.size() - 2;
std::vector<std::string> param_names;
for (i = 0; i < num_args; ++i) {
param_names.push_back(node->children[i+1]->text);
}
ss.register_function(boost::shared_ptr<dispatchkit::Proxy_Function>(
new dispatchkit::Dynamic_Proxy_Function(boost::bind(&eval_function<Eval_System>, boost::ref(ss), node->children.back(), param_names, _1))), node->children[0]->text);
}
break;
case (TokenType::Lambda_Def) : {
unsigned int num_args = node->children.size() - 1;
std::vector<std::string> param_names;
for (i = 0; i < num_args; ++i) {
param_names.push_back(node->children[i]->text);
}
//retval = boost::shared_ptr<dispatchkit::Proxy_Function>(new dispatchkit::Proxy_Function_Impl<boost::function<void (const std::string &)> >(&test));
retval = dispatchkit::Boxed_Value(boost::shared_ptr<dispatchkit::Proxy_Function>(
new dispatchkit::Dynamic_Proxy_Function(
boost::bind(&eval_function<Eval_System>, boost::ref(ss), node->children.back(), param_names, _1))));
}
break;
case (TokenType::Scoped_Block) : {
ss.new_scope();
for (i = 0; i < node->children.size(); ++i) {
retval = eval_token(ss, node->children[i]);
}
ss.pop_scope();
}
break;
case (TokenType::Return) : {
if (node->children.size() > 0) {
retval = eval_token(ss, node->children[0]);
}
else {
retval = dispatchkit::Boxed_Value();
}
throw ReturnValue(retval, node);
}
break;
case (TokenType::Break) : {
throw BreakLoop(node);
}
break;
case (TokenType::Statement) :
case (TokenType::Carriage_Return) :
case (TokenType::Semicolon) :
case (TokenType::Comment) :
case (TokenType::Operator) :
case (TokenType::Whitespace) :
case (TokenType::Parens_Open) :
case (TokenType::Parens_Close) :
case (TokenType::Square_Open) :
case (TokenType::Square_Close) :
case (TokenType::Curly_Open) :
case (TokenType::Curly_Close) :
case (TokenType::Comma) :
break;
}
return retval;
}
}
#endif /* CHAISCRIPT_EVAL_HPP_ */