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cpp-peglib/peglib.h
yhirose 553fc23853 Code clean up.
2015-06-13 01:20:33 -04:00

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//
// peglib.h
//
// Copyright (c) 2015 Yuji Hirose. All rights reserved.
// MIT License
//
#ifndef _CPPPEGLIB_PEGLIB_H_
#define _CPPPEGLIB_PEGLIB_H_
#include <algorithm>
#include <cassert>
#include <cstring>
#include <functional>
#include <initializer_list>
#include <iostream>
#include <limits>
#include <map>
#include <memory>
#include <mutex>
#include <set>
#include <string>
#include <unordered_map>
#include <vector>
namespace peglib {
extern void* enabler;
/*-----------------------------------------------------------------------------
* any
*---------------------------------------------------------------------------*/
class any
{
public:
any() : content_(nullptr) {}
any(const any& rhs) : content_(rhs.clone()) {}
any(any&& rhs) : content_(rhs.content_) {
rhs.content_ = nullptr;
}
template <typename T>
any(const T& value) : content_(new holder<T>(value)) {}
any& operator=(const any& rhs) {
if (this != &rhs) {
if (content_) {
delete content_;
}
content_ = rhs.clone();
}
return *this;
}
any& operator=(any&& rhs) {
if (this != &rhs) {
if (content_) {
delete content_;
}
content_ = rhs.content_;
rhs.content_ = nullptr;
}
return *this;
}
~any() {
delete content_;
}
bool is_undefined() const {
return content_ == nullptr;
}
template <
typename T,
typename std::enable_if<!std::is_same<T, any>::value>::type*& = enabler
>
T& get() {
if (!content_) {
throw std::bad_cast();
}
auto p = dynamic_cast<holder<T>*>(content_);
assert(p);
if (!p) {
throw std::bad_cast();
}
return p->value_;
}
template <
typename T,
typename std::enable_if<std::is_same<T, any>::value>::type*& = enabler
>
T& get() {
return *this;
}
template <
typename T,
typename std::enable_if<!std::is_same<T, any>::value>::type*& = enabler
>
const T& get() const {
assert(content_);
auto p = dynamic_cast<holder<T>*>(content_);
assert(p);
if (!p) {
throw std::bad_cast();
}
return p->value_;
}
template <
typename T,
typename std::enable_if<std::is_same<T, any>::value>::type*& = enabler
>
const any& get() const {
return *this;
}
private:
struct placeholder {
virtual ~placeholder() {};
virtual placeholder* clone() const = 0;
};
template <typename T>
struct holder : placeholder {
holder(const T& value) : value_(value) {}
placeholder* clone() const override {
return new holder(value_);
}
T value_;
};
placeholder* clone() const {
return content_ ? content_->clone() : nullptr;
}
placeholder* content_;
};
/*-----------------------------------------------------------------------------
* PEG
*---------------------------------------------------------------------------*/
/*
* Semantic values
*/
struct SemanticValue
{
any val;
const char* name;
const char* s;
size_t n;
SemanticValue()
: s(nullptr), n(0) {}
SemanticValue(const any& _val, const char* _name, const char* _s, size_t _n)
: val(_val), name(_name), s(_s), n(_n) {}
template <typename T>
T& get() {
return val.get<T>();
}
template <typename T>
const T& get() const {
return val.get<T>();
}
std::string str() const {
return std::string(s, n);
}
};
struct SemanticValues : protected std::vector<SemanticValue>
{
const char* s;
size_t n;
size_t choice;
SemanticValues() : s(nullptr), n(0), choice(0) {}
std::string str(size_t i = 0) const {
if (i > 0) {
return (*this)[i].str();
}
return std::string(s, n);
}
typedef SemanticValue T;
using std::vector<T>::iterator;
using std::vector<T>::const_iterator;
using std::vector<T>::size;
using std::vector<T>::empty;
using std::vector<T>::assign;
using std::vector<T>::begin;
using std::vector<T>::end;
using std::vector<T>::rbegin;
using std::vector<T>::rend;
using std::vector<T>::operator[];
using std::vector<T>::at;
using std::vector<T>::resize;
using std::vector<T>::front;
using std::vector<T>::back;
using std::vector<T>::push_back;
using std::vector<T>::pop_back;
using std::vector<T>::insert;
using std::vector<T>::erase;
using std::vector<T>::clear;
using std::vector<T>::swap;
using std::vector<T>::emplace;
using std::vector<T>::emplace_back;
template <typename F>
auto map(F f) const -> vector<typename std::remove_const<decltype(f(SemanticValue()))>::type> {
vector<typename std::remove_const<decltype(f(SemanticValue()))>::type> r;
for (const auto& v: *this) {
r.push_back(f(v));
}
return r;
}
template <typename F>
auto map(size_t beg, size_t end, F f) const -> vector<typename std::remove_const<decltype(f(SemanticValue()))>::type> {
vector<typename std::remove_const<decltype(f(SemanticValue()))>::type> r;
end = std::min(end, size());
for (size_t i = beg; i < end; i++) {
r.push_back(f((*this)[i]));
}
return r;
}
template <typename T>
auto map(size_t beg = 0, size_t end = -1) const -> vector<T> {
return this->map(beg, end, [](const SemanticValue& v) { return v.get<T>(); });
}
};
/*
* Semantic action
*/
template <
typename R, typename F,
typename std::enable_if<std::is_void<R>::value>::type*& = enabler,
typename... Args>
any call(F fn, Args&&... args) {
fn(std::forward<Args>(args)...);
return any();
}
template <
typename R, typename F,
typename std::enable_if<std::is_same<typename std::remove_cv<R>::type, any>::value>::type*& = enabler,
typename... Args>
any call(F fn, Args&&... args) {
return fn(std::forward<Args>(args)...);
}
template <
typename R, typename F,
typename std::enable_if<std::is_same<typename std::remove_cv<R>::type, SemanticValue>::value>::type*& = enabler,
typename... Args>
any call(F fn, Args&&... args) {
return fn(std::forward<Args>(args)...).val;
}
template <
typename R, typename F,
typename std::enable_if<
!std::is_void<R>::value &&
!std::is_same<typename std::remove_cv<R>::type, any>::value &&
!std::is_same<typename std::remove_cv<R>::type, SemanticValue>::value>::type*& = enabler,
typename... Args>
any call(F fn, Args&&... args) {
return any(fn(std::forward<Args>(args)...));
}
#if 0
/*
* Predicate
*/
typedef std::function<bool(const char* s, size_t n, const any& val, const any& dt)> Predicate;
#endif
class Action
{
public:
Action() = default;
Action(const Action& rhs) : fn_(rhs.fn_) {}
template <typename F, typename std::enable_if<!std::is_pointer<F>::value && !std::is_same<F, std::nullptr_t>::value>::type*& = enabler>
Action(F fn) : fn_(make_adaptor(fn, &F::operator())) {}
template <typename F, typename std::enable_if<std::is_pointer<F>::value>::type*& = enabler>
Action(F fn) : fn_(make_adaptor(fn, fn)) {}
template <typename F, typename std::enable_if<std::is_same<F, std::nullptr_t>::value>::type*& = enabler>
Action(F fn) {}
template <typename F, typename std::enable_if<!std::is_pointer<F>::value && !std::is_same<F, std::nullptr_t>::value>::type*& = enabler>
void operator=(F fn) {
fn_ = make_adaptor(fn, &F::operator());
}
template <typename F, typename std::enable_if<std::is_pointer<F>::value>::type*& = enabler>
void operator=(F fn) {
fn_ = make_adaptor(fn, fn);
}
template <typename F, typename std::enable_if<std::is_same<F, std::nullptr_t>::value>::type*& = enabler>
void operator=(F fn) {}
operator bool() const {
return (bool)fn_;
}
any operator()(const SemanticValues& sv, any& dt) const {
return fn_(sv, dt);
}
private:
template <typename R>
struct TypeAdaptor {
TypeAdaptor(std::function<R (const SemanticValues& sv)> fn)
: fn_(fn) {}
any operator()(const SemanticValues& sv, any& dt) {
return call<R>(fn_, sv);
}
std::function<R (const SemanticValues& sv)> fn_;
};
template <typename R>
struct TypeAdaptor_c {
TypeAdaptor_c(std::function<R (const SemanticValues& sv, any& dt)> fn)
: fn_(fn) {}
any operator()(const SemanticValues& sv, any& dt) {
return call<R>(fn_, sv, dt);
}
std::function<R (const SemanticValues& sv, any& dt)> fn_;
};
template <typename R>
struct TypeAdaptor_s_l {
TypeAdaptor_s_l(std::function<R (const char* s, size_t n)> fn) : fn_(fn) {}
any operator()(const SemanticValues& sv, any& dt) {
return call<R>(fn_, sv.s, sv.n);
}
std::function<R (const char* s, size_t n)> fn_;
};
template <typename R>
struct TypeAdaptor_empty {
TypeAdaptor_empty(std::function<R ()> fn) : fn_(fn) {}
any operator()(const SemanticValues& sv, any& dt) {
return call<R>(fn_);
}
std::function<R ()> fn_;
};
typedef std::function<any (const SemanticValues& sv, any& dt)> Fty;
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const SemanticValues& sv) const) {
return TypeAdaptor<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const SemanticValues& sv)) {
return TypeAdaptor<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R(*mf)(const SemanticValues& sv)) {
return TypeAdaptor<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const SemanticValues& sv, any& dt) const) {
return TypeAdaptor_c<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const SemanticValues& sv, any& dt)) {
return TypeAdaptor_c<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R(*mf)(const SemanticValues& sv, any& dt)) {
return TypeAdaptor_c<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const char*, size_t) const) {
return TypeAdaptor_s_l<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)(const char*, size_t)) {
return TypeAdaptor_s_l<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (*mf)(const char*, size_t)) {
return TypeAdaptor_s_l<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)() const) {
return TypeAdaptor_empty<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (F::*mf)()) {
return TypeAdaptor_empty<R>(fn);
}
template<typename F, typename R>
Fty make_adaptor(F fn, R (*mf)()) {
return TypeAdaptor_empty<R>(fn);
}
Fty fn_;
};
/*
* Match action
*/
typedef std::function<void (const char* s, size_t n, size_t id, const std::string& name)> MatchAction;
/*
* Result
*/
inline bool success(size_t len) {
return len != -1;
}
inline bool fail(size_t len) {
return len == -1;
}
/*
* Context
*/
struct Context
{
const char* s;
size_t l;
const char* error_pos;
const char* message_pos;
std::string message; // TODO: should be `int`.
size_t def_count;
std::vector<bool> cache_register;
std::vector<bool> cache_success;
std::map<std::pair<size_t, size_t>, std::tuple<size_t, any>> cache_result;
std::vector<std::shared_ptr<SemanticValues>> stack;
size_t stack_size;
Context(const char* _s, size_t _l, size_t _def_count, bool enablePackratParsing)
: s(_s)
, l(_l)
, error_pos(nullptr)
, message_pos(nullptr)
, def_count(_def_count)
, cache_register(enablePackratParsing ? def_count * (l + 1) : 0)
, cache_success(enablePackratParsing ? def_count * (l + 1) : 0)
, stack_size(0)
{
}
template <typename T>
void packrat(const char* s, size_t def_id, size_t& len, any& val, T fn) {
if (cache_register.empty()) {
fn(val);
return;
}
auto col = s - this->s;
auto has_cache = cache_register[def_count * col + def_id];
if (has_cache) {
if (cache_success[def_count * col + def_id]) {
const auto& key = std::make_pair(s - this->s, def_id);
std::tie(len, val) = cache_result[key];
return;
} else {
len = -1;
return;
}
} else {
fn(val);
cache_register[def_count * col + def_id] = true;
cache_success[def_count * col + def_id] = success(len);
if (success(len)) {
const auto& key = std::make_pair(s - this->s, def_id);
cache_result[key] = std::make_pair(len, val);
}
return;
}
}
inline SemanticValues& push() {
assert(stack_size <= stack.size());
if (stack_size == stack.size()) {
stack.push_back(std::make_shared<SemanticValues>());
}
auto& sv = *stack[stack_size++];
if (!sv.empty()) {
sv.clear();
}
sv.s = nullptr;
sv.n = 0;
return sv;
}
void pop() {
stack_size--;
}
void set_error_pos(const char* s) {
if (error_pos < s) error_pos = s;
}
};
/*
* Parser operators
*/
class Ope
{
public:
struct Visitor;
virtual ~Ope() {};
virtual size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const = 0;
virtual void accept(Visitor& v) = 0;
};
class Sequence : public Ope
{
public:
Sequence(const Sequence& rhs) : opes_(rhs.opes_) {}
#if defined(_MSC_VER) && _MSC_VER < 1900 // Less than Visual Studio 2015
// NOTE: Compiler Error C2797 on Visual Studio 2013
// "The C++ compiler in Visual Studio does not implement list
// initialization inside either a member initializer list or a non-static
// data member initializer. Before Visual Studio 2013 Update 3, this was
// silently converted to a function call, which could lead to bad code
// generation. Visual Studio 2013 Update 3 reports this as an error."
template <typename... Args>
Sequence(const Args& ...args) {
opes_ = std::vector<std::shared_ptr<Ope>>{ static_cast<std::shared_ptr<Ope>>(args)... };
}
#else
template <typename... Args>
Sequence(const Args& ...args) : opes_{ static_cast<std::shared_ptr<Ope>>(args)... } {}
#endif
Sequence(const std::vector<std::shared_ptr<Ope>>& opes) : opes_(opes) {}
Sequence(std::vector<std::shared_ptr<Ope>>&& opes) : opes_(std::move(opes)) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
size_t i = 0;
for (const auto& ope : opes_) {
const auto& rule = *ope;
auto len = rule.parse(s + i, n - i, sv, c, dt);
if (fail(len)) {
return -1;
}
i += len;
}
return i;
}
void accept(Visitor& v) override;
std::vector<std::shared_ptr<Ope>> opes_;
};
class PrioritizedChoice : public Ope
{
public:
#if defined(_MSC_VER) && _MSC_VER < 1900 // Less than Visual Studio 2015
// NOTE: Compiler Error C2797 on Visual Studio 2013
// "The C++ compiler in Visual Studio does not implement list
// initialization inside either a member initializer list or a non-static
// data member initializer. Before Visual Studio 2013 Update 3, this was
// silently converted to a function call, which could lead to bad code
// generation. Visual Studio 2013 Update 3 reports this as an error."
template <typename... Args>
PrioritizedChoice(const Args& ...args) {
opes_ = std::vector<std::shared_ptr<Ope>>{ static_cast<std::shared_ptr<Ope>>(args)... };
}
#else
template <typename... Args>
PrioritizedChoice(const Args& ...args) : opes_{ static_cast<std::shared_ptr<Ope>>(args)... } {}
#endif
PrioritizedChoice(const std::vector<std::shared_ptr<Ope>>& opes) : opes_(opes) {}
PrioritizedChoice(std::vector<std::shared_ptr<Ope>>&& opes) : opes_(std::move(opes)) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
size_t id = 0;
for (const auto& ope : opes_) {
const auto& rule = *ope;
auto& chldsv = c.push();
auto len = rule.parse(s, n, chldsv, c, dt);
if (len != -1) {
if (!chldsv.empty()) {
sv.insert(sv.end(), chldsv.begin(), chldsv.end());
}
sv.s = chldsv.s;
sv.n = chldsv.n;
sv.choice = id;
c.pop();
return len;
}
id++;
c.pop();
}
return -1;
}
void accept(Visitor& v) override;
size_t size() const { return opes_.size(); }
std::vector<std::shared_ptr<Ope>> opes_;
};
class ZeroOrMore : public Ope
{
public:
ZeroOrMore(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
auto i = 0;
while (n - i > 0) {
const auto& rule = *ope_;
auto len = rule.parse(s + i, n - i, sv, c, dt);
if (fail(len)) {
break;
}
i += len;
}
return i;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class OneOrMore : public Ope
{
public:
OneOrMore(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto len = rule.parse(s, n, sv, c, dt);
if (fail(len)) {
return -1;
}
auto i = len;
while (n - i > 0) {
const auto& rule = *ope_;
auto len = rule.parse(s + i, n - i, sv, c, dt);
if (fail(len)) {
break;
}
i += len;
}
return i;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class Option : public Ope
{
public:
Option(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto len = rule.parse(s, n, sv, c, dt);
return success(len) ? len : 0;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class AndPredicate : public Ope
{
public:
AndPredicate(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto& chldsv = c.push();
auto len = rule.parse(s, n, chldsv, c, dt);
c.pop();
if (success(len)) {
return 0;
} else {
return -1;
}
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class NotPredicate : public Ope
{
public:
NotPredicate(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto error_pos = c.error_pos;
auto len = rule.parse(s, n, sv, c, dt);
if (success(len)) {
c.set_error_pos(s);
return -1;
} else {
c.error_pos = error_pos;
return 0;
}
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class LiteralString : public Ope
{
public:
LiteralString(const std::string& s) : lit_(s) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
auto i = 0u;
for (; i < lit_.size(); i++) {
if (i >= n || s[i] != lit_[i]) {
c.set_error_pos(s);
return -1;
}
}
return i;
}
void accept(Visitor& v) override;
std::string lit_;
};
class CharacterClass : public Ope
{
public:
CharacterClass(const std::string& chars) : chars_(chars) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
// TODO: UTF8 support
if (n < 1) {
c.set_error_pos(s);
return -1;
}
auto ch = s[0];
auto i = 0u;
while (i < chars_.size()) {
if (i + 2 < chars_.size() && chars_[i + 1] == '-') {
if (chars_[i] <= ch && ch <= chars_[i + 2]) {
return 1;
}
i += 3;
} else {
if (chars_[i] == ch) {
return 1;
}
i += 1;
}
}
c.set_error_pos(s);
return -1;
}
void accept(Visitor& v) override;
std::string chars_;
};
class Character : public Ope
{
public:
Character(char ch) : ch_(ch) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
// TODO: UTF8 support
if (n < 1 || s[0] != ch_) {
c.set_error_pos(s);
return -1;
}
return 1;
}
void accept(Visitor& v) override;
char ch_;
};
class AnyCharacter : public Ope
{
public:
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
// TODO: UTF8 support
if (n < 1) {
c.set_error_pos(s);
return -1;
}
return 1;
}
void accept(Visitor& v) override;
};
class Capture : public Ope
{
public:
Capture(const std::shared_ptr<Ope>& ope, MatchAction ma, size_t id, const std::string& name)
: ope_(ope), match_action_(ma), id_(id), name_(name) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto len = rule.parse(s, n, sv, c, dt);
if (success(len) && match_action_) {
match_action_(s, len, id_, name_);
}
return len;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
private:
MatchAction match_action_;
size_t id_;
std::string name_;
};
class Anchor : public Ope
{
public:
Anchor(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto len = rule.parse(s, n, sv, c, dt);
if (success(len)) {
sv.s = s;
sv.n = len;
}
return len;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
class Ignore : public Ope
{
public:
Ignore(const std::shared_ptr<Ope>& ope) : ope_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
const auto& rule = *ope_;
auto& chldsv = c.push();
auto len = rule.parse(s, n, chldsv, c, dt);
c.pop();
return len;
}
void accept(Visitor& v) override;
std::shared_ptr<Ope> ope_;
};
typedef std::function<size_t(const char* s, size_t n, SemanticValues& sv, any& dt)> Parser;
class User : public Ope
{
public:
User(Parser fn) : fn_(fn) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
assert(fn_);
return fn_(s, n, sv, dt);
}
void accept(Visitor& v) override;
std::function<size_t(const char* s, size_t n, SemanticValues& sv, any& dt)> fn_;
};
class WeakHolder : public Ope
{
public:
WeakHolder(const std::shared_ptr<Ope>& ope) : weak_(ope) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override {
auto ope = weak_.lock();
assert(ope);
const auto& rule = *ope;
return rule.parse(s, n, sv, c, dt);
}
void accept(Visitor& v) override;
std::weak_ptr<Ope> weak_;
};
class Definition;
class Holder : public Ope
{
public:
Holder(Definition* outer)
: outer_(outer) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override;
void accept(Visitor& v) override;
any reduce(const SemanticValues& sv, any& dt, const Action& action) const;
std::shared_ptr<Ope> ope_;
Definition* outer_;
friend class Definition;
};
class DefinitionReference : public Ope
{
public:
DefinitionReference(
const std::unordered_map<std::string, Definition>& grammar, const std::string& name, const char* s)
: grammar_(grammar)
, name_(name)
, s_(s) {}
size_t parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const override;
void accept(Visitor& v) override;
std::shared_ptr<Ope> get_rule() const;
const std::unordered_map<std::string, Definition>& grammar_;
const std::string name_;
const char* s_;
private:
mutable std::once_flag init_;
mutable std::shared_ptr<Ope> rule_;
};
/*
* Visitor
*/
struct Ope::Visitor
{
virtual void visit(Sequence& ope) {}
virtual void visit(PrioritizedChoice& ope) {}
virtual void visit(ZeroOrMore& ope) {}
virtual void visit(OneOrMore& ope) {}
virtual void visit(Option& ope) {}
virtual void visit(AndPredicate& ope) {}
virtual void visit(NotPredicate& ope) {}
virtual void visit(LiteralString& ope) {}
virtual void visit(CharacterClass& ope) {}
virtual void visit(Character& ope) {}
virtual void visit(AnyCharacter& ope) {}
virtual void visit(Capture& ope) {}
virtual void visit(Anchor& ope) {}
virtual void visit(Ignore& ope) {}
virtual void visit(User& ope) {}
virtual void visit(WeakHolder& ope) {}
virtual void visit(Holder& ope) {}
virtual void visit(DefinitionReference& ope) {}
};
struct AssignIDToDefinition : public Ope::Visitor
{
void visit(Sequence& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
}
}
void visit(PrioritizedChoice& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
}
}
void visit(ZeroOrMore& ope) override { ope.ope_->accept(*this); }
void visit(OneOrMore& ope) override { ope.ope_->accept(*this); }
void visit(Option& ope) override { ope.ope_->accept(*this); }
void visit(AndPredicate& ope) override { ope.ope_->accept(*this); }
void visit(NotPredicate& ope) override { ope.ope_->accept(*this); }
void visit(Capture& ope) override { ope.ope_->accept(*this); }
void visit(Anchor& ope) override { ope.ope_->accept(*this); }
void visit(Ignore& ope) override { ope.ope_->accept(*this); }
void visit(WeakHolder& ope) override { ope.weak_.lock()->accept(*this); }
void visit(Holder& ope) override;
void visit(DefinitionReference& ope) override { ope.get_rule()->accept(*this); }
std::unordered_map<void*, size_t> ids;
};
struct IsToken : public Ope::Visitor
{
IsToken() : has_anchor(false), has_rule(false) {}
void visit(Sequence& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
}
}
void visit(PrioritizedChoice& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
}
}
void visit(ZeroOrMore& ope) override { ope.ope_->accept(*this); }
void visit(OneOrMore& ope) override { ope.ope_->accept(*this); }
void visit(Option& ope) override { ope.ope_->accept(*this); }
void visit(Capture& ope) override { ope.ope_->accept(*this); }
void visit(Anchor& ope) override { has_anchor = true; }
void visit(Ignore& ope) override { ope.ope_->accept(*this); }
void visit(WeakHolder& ope) override { ope.weak_.lock()->accept(*this); }
void visit(DefinitionReference& ope) override { has_rule = true; }
bool is_token() const {
return has_anchor || !has_rule;
}
bool has_anchor;
bool has_rule;
};
/*
* Definition
*/
class Definition
{
public:
struct Result {
bool ret;
size_t len;
const char* error_pos;
const char* message_pos;
const std::string message;
};
Definition()
: actions(1)
, ignoreSemanticValue(false)
, enablePackratParsing(false)
, is_token(false)
, holder_(std::make_shared<Holder>(this)) {}
Definition(const Definition& rhs)
: name(rhs.name)
, actions(1)
, ignoreSemanticValue(false)
, enablePackratParsing(false)
, is_token(false)
, holder_(rhs.holder_)
{
holder_->outer_ = this;
}
Definition(Definition&& rhs)
: name(std::move(rhs.name))
, actions(1)
, ignoreSemanticValue(rhs.ignoreSemanticValue)
, enablePackratParsing(rhs.enablePackratParsing)
, is_token(rhs.is_token)
, holder_(std::move(rhs.holder_))
{
holder_->outer_ = this;
}
Definition(const std::shared_ptr<Ope>& ope)
: actions(1)
, ignoreSemanticValue(false)
, enablePackratParsing(false)
, is_token(false)
, holder_(std::make_shared<Holder>(this))
{
*this <= ope;
}
operator std::shared_ptr<Ope>() {
return std::make_shared<WeakHolder>(holder_);
}
Definition& operator<=(const std::shared_ptr<Ope>& ope) {
IsToken isToken;
ope->accept(isToken);
is_token = isToken.is_token();
holder_->ope_ = ope;
return *this;
}
Result parse(const char* s, size_t n) const {
SemanticValues sv;
any dt;
return parse_core(s, n, sv, dt);
}
Result parse(const char* s) const {
auto n = strlen(s);
return parse(s, n);
}
Result parse(const char* s, size_t n, any& dt) const {
SemanticValues sv;
return parse_core(s, n, sv, dt);
}
Result parse(const char* s, any& dt) const {
auto n = strlen(s);
return parse(s, n, dt);
}
template <typename T>
Result parse_and_get_value(const char* s, size_t n, T& val) const {
SemanticValues sv;
any dt;
auto r = parse_core(s, n, sv, dt);
if (r.ret && !sv.empty() && !sv.front().val.is_undefined()) {
val = sv[0].val.get<T>();
}
return r;
}
template <typename T>
Result parse_and_get_value(const char* s, T& val) const {
auto n = strlen(s);
return parse_and_get_value(s, n, val);
}
template <typename T>
Result parse_and_get_value(const char* s, size_t n, any& dt, T& val) const {
SemanticValues sv;
auto r = parse_core(s, n, sv, dt);
if (r.ret && !sv.empty() && !sv.front().val.is_undefined()) {
val = sv[0].val.get<T>();
}
return r;
}
template <typename T>
Result parse_and_get_value(const char* s, any& dt, T& val) const {
auto n = strlen(s);
return parse_and_get_value(s, n, dt, val);
}
Definition& operator=(Action action) {
assert(!actions.empty());
actions[0] = action;
return *this;
}
Definition& operator=(std::initializer_list<Action> ini) {
actions = ini;
return *this;
}
template <typename T>
Definition& operator,(T fn) {
operator=(fn);
return *this;
}
Definition& operator~() {
ignoreSemanticValue = true;
return *this;
}
void accept(Ope::Visitor& v) {
holder_->accept(v);
}
std::string name;
size_t id;
#if 0
Predicate predicate;
#endif
std::vector<Action> actions;
std::function<std::string ()> error_message;
bool ignoreSemanticValue;
bool enablePackratParsing;
bool is_token;
private:
friend class DefinitionReference;
Definition& operator=(const Definition& rhs);
Definition& operator=(Definition&& rhs);
Result parse_core(const char* s, size_t n, SemanticValues& sv, any& dt) const {
AssignIDToDefinition assignId;
holder_->accept(assignId);
Context cxt(s, n, assignId.ids.size(), enablePackratParsing);
auto len = holder_->parse(s, n, sv, cxt, dt);
return Result{ success(len), len, cxt.error_pos, cxt.message_pos, cxt.message };
}
std::shared_ptr<Holder> holder_;
};
/*
* Implementations
*/
inline size_t Holder::parse(const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const {
if (!ope_) {
throw std::logic_error("Uninitialized definition ope was used...");
}
size_t len;
any val;
const char* anchors = s;
size_t anchorn = n;
c.packrat(s, outer_->id, len, val, [&](any& val) {
auto& chldsv = c.push();
const auto& rule = *ope_;
len = rule.parse(s, n, chldsv, c, dt);
anchorn = len;
// Invoke action
if (success(len) && !outer_->ignoreSemanticValue) {
assert(!outer_->actions.empty());
auto i = chldsv.choice + 1; // Index 0 is for the default action
const auto& action = (i < outer_->actions.size() && outer_->actions[i])
? outer_->actions[i]
: outer_->actions[0];
if (chldsv.s) {
anchors = chldsv.s;
anchorn = chldsv.n;
} else {
chldsv.s = s;
chldsv.n = len;
}
val = reduce(chldsv, dt, action);
}
#if 0
// Predicate check
if (success(len) && outer_->predicate && !outer_->predicate(anchors, anchorn, val, dt)) {
len = -1;
}
#endif
c.pop();
});
if (success(len) && !outer_->ignoreSemanticValue) {
sv.emplace_back(val, outer_->name.c_str(), anchors, anchorn);
}
if (fail(len) && outer_->error_message && !c.message_pos) {
c.message_pos = s;
c.message = outer_->error_message();
}
return len;
}
inline any Holder::reduce(const SemanticValues& sv, any& dt, const Action& action) const {
if (action) {
return action(sv, dt);
} else if (sv.empty()) {
return any();
} else {
return sv.front().val;
}
}
inline size_t DefinitionReference::parse(
const char* s, size_t n, SemanticValues& sv, Context& c, any& dt) const {
const auto& rule = *get_rule();
return rule.parse(s, n, sv, c, dt);
}
inline std::shared_ptr<Ope> DefinitionReference::get_rule() const {
if (!rule_) {
std::call_once(init_, [this]() {
rule_ = grammar_.at(name_).holder_;
});
}
assert(rule_);
return rule_;
};
inline void Sequence::accept(Visitor& v) { v.visit(*this); }
inline void PrioritizedChoice::accept(Visitor& v) { v.visit(*this); }
inline void ZeroOrMore::accept(Visitor& v) { v.visit(*this); }
inline void OneOrMore::accept(Visitor& v) { v.visit(*this); }
inline void Option::accept(Visitor& v) { v.visit(*this); }
inline void AndPredicate::accept(Visitor& v) { v.visit(*this); }
inline void NotPredicate::accept(Visitor& v) { v.visit(*this); }
inline void LiteralString::accept(Visitor& v) { v.visit(*this); }
inline void CharacterClass::accept(Visitor& v) { v.visit(*this); }
inline void Character::accept(Visitor& v) { v.visit(*this); }
inline void AnyCharacter::accept(Visitor& v) { v.visit(*this); }
inline void Capture::accept(Visitor& v) { v.visit(*this); }
inline void Anchor::accept(Visitor& v) { v.visit(*this); }
inline void Ignore::accept(Visitor& v) { v.visit(*this); }
inline void User::accept(Visitor& v) { v.visit(*this); }
inline void WeakHolder::accept(Visitor& v) { v.visit(*this); }
inline void Holder::accept(Visitor& v) { v.visit(*this); }
inline void DefinitionReference::accept(Visitor& v) { v.visit(*this); }
inline void AssignIDToDefinition::visit(Holder& ope) {
auto p = (void*)ope.outer_;
if (ids.find(p) != ids.end()) {
return;
}
auto id = ids.size();
ids[p] = id;
ope.outer_->id = id;
ope.ope_->accept(*this);
}
/*
* Factories
*/
template <typename... Args>
std::shared_ptr<Ope> seq(Args&& ...args) {
return std::make_shared<Sequence>(static_cast<std::shared_ptr<Ope>>(args)...);
}
template <typename... Args>
std::shared_ptr<Ope> cho(Args&& ...args) {
return std::make_shared<PrioritizedChoice>(static_cast<std::shared_ptr<Ope>>(args)...);
}
inline std::shared_ptr<Ope> zom(const std::shared_ptr<Ope>& ope) {
return std::make_shared<ZeroOrMore>(ope);
}
inline std::shared_ptr<Ope> oom(const std::shared_ptr<Ope>& ope) {
return std::make_shared<OneOrMore>(ope);
}
inline std::shared_ptr<Ope> opt(const std::shared_ptr<Ope>& ope) {
return std::make_shared<Option>(ope);
}
inline std::shared_ptr<Ope> apd(const std::shared_ptr<Ope>& ope) {
return std::make_shared<AndPredicate>(ope);
}
inline std::shared_ptr<Ope> npd(const std::shared_ptr<Ope>& ope) {
return std::make_shared<NotPredicate>(ope);
}
inline std::shared_ptr<Ope> lit(const std::string& lit) {
return std::make_shared<LiteralString>(lit);
}
inline std::shared_ptr<Ope> cls(const std::string& chars) {
return std::make_shared<CharacterClass>(chars);
}
inline std::shared_ptr<Ope> chr(char dt) {
return std::make_shared<Character>(dt);
}
inline std::shared_ptr<Ope> dot() {
return std::make_shared<AnyCharacter>();
}
inline std::shared_ptr<Ope> cap(const std::shared_ptr<Ope>& ope, MatchAction ma, size_t n, const std::string& s) {
return std::make_shared<Capture>(ope, ma, n, s);
}
inline std::shared_ptr<Ope> cap(const std::shared_ptr<Ope>& ope, MatchAction ma) {
return std::make_shared<Capture>(ope, ma, (size_t)-1, std::string());
}
inline std::shared_ptr<Ope> anc(const std::shared_ptr<Ope>& ope) {
return std::make_shared<Anchor>(ope);
}
inline std::shared_ptr<Ope> ign(const std::shared_ptr<Ope>& ope) {
return std::make_shared<Ignore>(ope);
}
inline std::shared_ptr<Ope> usr(std::function<size_t (const char* s, size_t n, SemanticValues& sv, any& dt)> fn) {
return std::make_shared<User>(fn);
}
inline std::shared_ptr<Ope> ref(const std::unordered_map<std::string, Definition>& grammar, const std::string& name, const char* s) {
return std::make_shared<DefinitionReference>(grammar, name, s);
}
/*-----------------------------------------------------------------------------
* PEG parser generator
*---------------------------------------------------------------------------*/
inline std::pair<size_t, size_t> line_info(const char* start, const char* cur) {
auto p = start;
auto col_ptr = p;
auto no = 1;
while (p < cur) {
if (*p == '\n') {
no++;
col_ptr = p + 1;
}
p++;
}
auto col = p - col_ptr + 1;
return std::make_pair(no, col);
}
typedef std::unordered_map<std::string, Definition> Grammar;
typedef std::function<void (size_t, size_t, const std::string&)> Log;
typedef std::unordered_map<std::string, std::shared_ptr<Ope>> Rules;
class PEGParser
{
public:
static std::shared_ptr<Grammar> parse(
const char* s,
size_t n,
const Rules& rules,
std::string& start,
MatchAction ma,
Log log)
{
return get_instance().perform_core(s, n, rules, start, ma, log);
}
static std::shared_ptr<Grammar> parse(
const char* s,
size_t n,
std::string& start,
MatchAction ma,
Log log)
{
Rules dummy;
return parse(s, n, dummy, start, ma, log);
}
// For debuging purpose
static Grammar& grammar() {
return get_instance().g;
}
private:
static PEGParser& get_instance() {
static PEGParser instance;
return instance;
}
PEGParser() {
make_grammar();
setup_actions();
}
struct Data {
std::shared_ptr<Grammar> grammar;
std::string start;
MatchAction match_action;
std::vector<std::pair<std::string, const char*>> duplicates;
std::unordered_map<std::string, const char*> references;
size_t capture_count;
Data()
: grammar(std::make_shared<Grammar>())
, capture_count(0)
{}
};
struct DetectLeftRecursion : public Ope::Visitor {
DetectLeftRecursion(const std::string& name)
: s_(nullptr), name_(name), done_(false) {}
void visit(Sequence& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
if (done_) {
break;
} else if (s_) {
done_ = true;
break;
}
}
}
void visit(PrioritizedChoice& ope) override {
for (auto ope: ope.opes_) {
ope->accept(*this);
if (s_) {
done_ = true;
break;
}
}
}
void visit(ZeroOrMore& ope) override {
ope.ope_->accept(*this);
done_ = false;
}
void visit(OneOrMore& ope) override {
ope.ope_->accept(*this);
done_ = true;
}
void visit(Option& ope) override {
ope.ope_->accept(*this);
done_ = false;
}
void visit(AndPredicate& ope) override {
ope.ope_->accept(*this);
done_ = false;
}
void visit(NotPredicate& ope) override {
ope.ope_->accept(*this);
done_ = false;
}
void visit(LiteralString& ope) override {
done_ = !ope.lit_.empty();
}
void visit(CharacterClass& ope) override {
done_ = true;
}
void visit(Character& ope) override {
done_ = true;
}
void visit(AnyCharacter& ope) override {
done_ = true;
}
void visit(Capture& ope) override {
ope.ope_->accept(*this);
}
void visit(Anchor& ope) override {
ope.ope_->accept(*this);
}
void visit(Ignore& ope) override {
ope.ope_->accept(*this);
}
void visit(User& ope) override {
done_ = true;
}
void visit(WeakHolder& ope) override {
ope.weak_.lock()->accept(*this);
}
void visit(Holder& ope) override {
ope.ope_->accept(*this);
}
void visit(DefinitionReference& ope) override {
if (ope.name_ == name_) {
s_ = ope.s_;
} else if (refs_.find(ope.name_) != refs_.end()) {
;
} else {
refs_.insert(ope.name_);
ope.get_rule()->accept(*this);
}
done_ = true;
}
const char* s_;
private:
std::string name_;
std::set<std::string> refs_;
bool done_;
};
void make_grammar() {
// Setup PEG syntax parser
g["Grammar"] <= seq(g["Spacing"], oom(g["Definition"]), g["EndOfFile"]);
g["Definition"] <= seq(opt(g["IGNORE"]), g["Identifier"], g["LEFTARROW"], g["Expression"]);
g["Expression"] <= seq(g["Sequence"], zom(seq(g["SLASH"], g["Sequence"])));
g["Sequence"] <= zom(g["Prefix"]);
g["Prefix"] <= seq(opt(cho(g["AND"], g["NOT"])), g["Suffix"]);
g["Suffix"] <= seq(g["Primary"], opt(cho(g["QUESTION"], g["STAR"], g["PLUS"])));
g["Primary"] <= cho(seq(opt(g["IGNORE"]), g["Identifier"], npd(g["LEFTARROW"])),
seq(g["OPEN"], g["Expression"], g["CLOSE"]),
seq(g["Begin"], g["Expression"], g["End"]),
seq(g["BeginCap"], g["Expression"], g["EndCap"]),
g["Literal"], g["Class"], g["DOT"]);
g["Identifier"] <= seq(g["IdentCont"], g["Spacing"]);
g["IdentCont"] <= seq(g["IdentStart"], zom(g["IdentRest"]));
g["IdentStart"] <= cls("a-zA-Z_");
g["IdentRest"] <= cho(g["IdentStart"], cls("0-9"));
g["Literal"] <= cho(seq(cls("'"), anc(zom(seq(npd(cls("'")), g["Char"]))), cls("'"), g["Spacing"]),
seq(cls("\""), anc(zom(seq(npd(cls("\"")), g["Char"]))), cls("\""), g["Spacing"]));
g["Class"] <= seq(chr('['), anc(zom(seq(npd(chr(']')), g["Range"]))), chr(']'), g["Spacing"]);
g["Range"] <= cho(seq(g["Char"], chr('-'), g["Char"]), g["Char"]);
g["Char"] <= cho(seq(chr('\\'), cls("nrt'\"[]\\")),
seq(chr('\\'), cls("0-3"), cls("0-7"), cls("0-7")),
seq(chr('\\'), cls("0-7"), opt(cls("0-7"))),
seq(lit("\\x"), cls("0-9a-fA-F"), opt(cls("0-9a-fA-F"))),
seq(npd(chr('\\')), dot()));
g["LEFTARROW"] <= seq(lit("<-"), g["Spacing"]);
~g["SLASH"] <= seq(chr('/'), g["Spacing"]);
g["AND"] <= seq(chr('&'), g["Spacing"]);
g["NOT"] <= seq(chr('!'), g["Spacing"]);
g["QUESTION"] <= seq(chr('?'), g["Spacing"]);
g["STAR"] <= seq(chr('*'), g["Spacing"]);
g["PLUS"] <= seq(chr('+'), g["Spacing"]);
g["OPEN"] <= seq(chr('('), g["Spacing"]);
g["CLOSE"] <= seq(chr(')'), g["Spacing"]);
g["DOT"] <= seq(chr('.'), g["Spacing"]);
g["Spacing"] <= zom(cho(g["Space"], g["Comment"]));
g["Comment"] <= seq(chr('#'), zom(seq(npd(g["EndOfLine"]), dot())), g["EndOfLine"]);
g["Space"] <= cho(chr(' '), chr('\t'), g["EndOfLine"]);
g["EndOfLine"] <= cho(lit("\r\n"), chr('\n'), chr('\r'));
g["EndOfFile"] <= npd(dot());
g["Begin"] <= seq(chr('<'), g["Spacing"]);
g["End"] <= seq(chr('>'), g["Spacing"]);
g["BeginCap"] <= seq(chr('$'), anc(opt(g["Identifier"])), chr('<'), g["Spacing"]);
g["EndCap"] <= seq(lit(">"), g["Spacing"]);
g["IGNORE"] <= chr('~');
// Set definition names
for (auto& x: g) {
x.second.name = x.first;
}
}
void setup_actions() {
g["Definition"] = [&](const SemanticValues& sv, any& dt) {
Data& data = *dt.get<Data*>();
auto ignore = (sv.size() == 4);
auto baseId = ignore ? 1 : 0;
const auto& name = sv[baseId].val.get<std::string>();
auto ope = sv[baseId + 2].val.get<std::shared_ptr<Ope>>();
auto& grammar = *data.grammar;
if (grammar.find(name) == grammar.end()) {
auto& rule = grammar[name];
rule <= ope;
rule.name = name;
rule.ignoreSemanticValue = ignore;
if (data.start.empty()) {
data.start = name;
}
} else {
data.duplicates.push_back(std::make_pair(name, sv.s));
}
};
g["Expression"] = [&](const SemanticValues& sv) {
if (sv.size() == 1) {
return sv[0].val.get<std::shared_ptr<Ope>>();
} else {
std::vector<std::shared_ptr<Ope>> opes;
for (auto i = 0u; i < sv.size(); i++) {
opes.push_back(sv[i].val.get<std::shared_ptr<Ope>>());
}
const std::shared_ptr<Ope> ope = std::make_shared<PrioritizedChoice>(opes);
return ope;
}
};
g["Sequence"] = [&](const SemanticValues& sv) {
if (sv.size() == 1) {
return sv[0].val.get<std::shared_ptr<Ope>>();
} else {
std::vector<std::shared_ptr<Ope>> opes;
for (const auto& x: sv) {
opes.push_back(x.val.get<std::shared_ptr<Ope>>());
}
const std::shared_ptr<Ope> ope = std::make_shared<Sequence>(opes);
return ope;
}
};
g["Prefix"] = [&](const SemanticValues& sv) {
std::shared_ptr<Ope> ope;
if (sv.size() == 1) {
ope = sv[0].val.get<std::shared_ptr<Ope>>();
} else {
assert(sv.size() == 2);
auto tok = sv[0].val.get<char>();
ope = sv[1].val.get<std::shared_ptr<Ope>>();
if (tok == '&') {
ope = apd(ope);
} else { // '!'
ope = npd(ope);
}
}
return ope;
};
g["Suffix"] = [&](const SemanticValues& sv) {
auto ope = sv[0].val.get<std::shared_ptr<Ope>>();
if (sv.size() == 1) {
return ope;
} else {
assert(sv.size() == 2);
auto tok = sv[1].val.get<char>();
if (tok == '?') {
return opt(ope);
} else if (tok == '*') {
return zom(ope);
} else { // '+'
return oom(ope);
}
}
};
g["Primary"].actions = {
// Default
[&](const SemanticValues& sv) {
return sv[0];
},
// Reference
[&](const SemanticValues& sv, any& dt) {
Data& data = *dt.get<Data*>();
auto ignore = (sv.size() == 2);
auto baseId = ignore ? 1 : 0;
const auto& ident = sv[baseId].val.get<std::string>();
if (data.references.find(ident) == data.references.end()) {
data.references[ident] = sv.s; // for error handling
}
if (ignore) {
return ign(ref(*data.grammar, ident, sv.s));
} else {
return ref(*data.grammar, ident, sv.s);
}
},
// (Expression)
[&](const SemanticValues& sv) {
return sv[1];
},
// Anchor
[&](const SemanticValues& sv) {
auto ope = sv[1].val.get<std::shared_ptr<Ope>>();
return anc(ope);
},
// Capture
[&](const SemanticValues& sv, any& dt) {
Data& data = *dt.get<Data*>();
auto name = std::string(sv[0].s, sv[0].n);
auto ope = sv[1].val.get<std::shared_ptr<Ope>>();
return cap(ope, data.match_action, ++data.capture_count, name);
}
};
g["IdentCont"] = [](const char* s, size_t n) {
return std::string(s, n);
};
g["Literal"] = [this](const char* s, size_t n) {
return lit(resolve_escape_sequence(s, n));
};
g["Class"] = [this](const char* s, size_t n) {
return cls(resolve_escape_sequence(s, n));
};
g["AND"] = [](const char* s, size_t n) { return *s; };
g["NOT"] = [](const char* s, size_t n) { return *s; };
g["QUESTION"] = [](const char* s, size_t n) { return *s; };
g["STAR"] = [](const char* s, size_t n) { return *s; };
g["PLUS"] = [](const char* s, size_t n) { return *s; };
g["DOT"] = []() { return dot(); };
}
std::shared_ptr<Grammar> perform_core(
const char* s,
size_t n,
const Rules& rules,
std::string& start,
MatchAction ma,
Log log)
{
Data data;
data.match_action = ma;
any dt = &data;
auto r = g["Grammar"].parse(s, n, dt);
if (!r.ret) {
if (log) {
auto line = line_info(s, r.error_pos);
log(line.first, line.second, r.message.empty() ? "syntax error" : r.message);
}
return nullptr;
}
auto& grammar = *data.grammar;
// User provided rules
for (const auto& x: rules) {
auto name = x.first;
bool ignore = false;
if (!name.empty() && name[0] == '~') {
ignore = true;
name.erase(0, 1);
}
if (!name.empty()) {
auto& rule = grammar[name];
rule <= x.second;
rule.name = name;
rule.ignoreSemanticValue = ignore;
}
}
// Check duplicated definitions
bool ret = data.duplicates.empty();;
for (const auto& x: data.duplicates) {
if (log) {
const auto& name = x.first;
auto ptr = x.second;
auto line = line_info(s, ptr);
log(line.first, line.second, "'" + name + "' is already defined.");
}
}
// Check missing definitions
for (const auto& x : data.references) {
const auto& name = x.first;
auto ptr = x.second;
if (grammar.find(name) == grammar.end()) {
if (log) {
auto line = line_info(s, ptr);
log(line.first, line.second, "'" + name + "' is not defined.");
}
ret = false;
}
}
if (!ret) {
return nullptr;
}
// Check left recursion
ret = true;
for (auto& x: grammar) {
const auto& name = x.first;
auto& rule = x.second;
DetectLeftRecursion lr(name);
rule.accept(lr);
if (lr.s_) {
if (log) {
auto line = line_info(s, lr.s_);
log(line.first, line.second, "'" + name + "' is left recursive.");
}
ret = false;;
}
}
if (!ret) {
return nullptr;
}
// Set root definition
start = data.start;
return data.grammar;
}
bool is_hex(char c, int& v) {
if ('0' <= c && c <= '9') {
v = c - '0';
return true;
} else if ('a' <= c && c <= 'f') {
v = c - 'a' + 10;
return true;
} else if ('A' <= c && c <= 'F') {
v = c - 'A' + 10;
return true;
}
return false;
}
bool is_digit(char c, int& v) {
if ('0' <= c && c <= '9') {
v = c - '0';
return true;
}
return false;
}
std::pair<char, size_t> parse_hex_number(const char* s, size_t n, size_t i) {
char ret = 0;
int val;
while (i < n && is_hex(s[i], val)) {
ret = ret * 16 + val;
i++;
}
return std::make_pair(ret, i);
}
std::pair<char, size_t> parse_octal_number(const char* s, size_t n, size_t i) {
char ret = 0;
int val;
while (i < n && is_digit(s[i], val)) {
ret = ret * 8 + val;
i++;
}
return std::make_pair(ret, i);
}
std::string resolve_escape_sequence(const char* s, size_t n) {
std::string r;
r.reserve(n);
auto i = 0u;
while (i < n) {
auto ch = s[i];
if (ch == '\\') {
i++;
switch (s[i]) {
case 'n': r += '\n'; i++; break;
case 'r': r += '\r'; i++; break;
case 't': r += '\t'; i++; break;
case '\'': r += '\''; i++; break;
case '"': r += '"'; i++; break;
case '[': r += '['; i++; break;
case ']': r += ']'; i++; break;
case '\\': r += '\\'; i++; break;
case 'x': {
std::tie(ch, i) = parse_hex_number(s, n, i + 1);
r += ch;
break;
}
default: {
std::tie(ch, i) = parse_octal_number(s, n, i);
r += ch;
break;
}
}
} else {
r += ch;
i++;
}
}
return r;
}
Grammar g;
};
/*-----------------------------------------------------------------------------
* AST
*---------------------------------------------------------------------------*/
const int AstDefaultTag = -1;
struct Ast
{
Ast(const char* _name, int _tag, const std::vector<std::shared_ptr<Ast>>& _nodes)
: name(_name), tag(_tag), is_token(false), nodes(_nodes) {}
Ast(const char* _name, int _tag, const std::string& _token)
: name(_name), tag(_tag), is_token(true), token(_token) {}
void print() const;
const std::string name;
const int tag;
const bool is_token;
const std::string token;
const std::vector<std::shared_ptr<Ast>> nodes;
};
struct AstPrint
{
AstPrint() : level_(-1) {}
void print(const Ast& ast) {
level_ += 1;
for (auto i = 0; i < level_; i++) { std::cout << " "; }
if (ast.is_token) {
std::cout << "- " << ast.name << ": '" << ast.token << "'" << std::endl;
} else {
std::cout << "+ " << ast.name << std::endl;
}
for (auto node : ast.nodes) { print(*node); }
level_ -= 1;
}
private:
int level_;
};
inline void Ast::print() const {
AstPrint().print(*this);
}
/*-----------------------------------------------------------------------------
* peg
*---------------------------------------------------------------------------*/
class peg
{
public:
peg() = default;
peg(const char* s, size_t n, const Rules& rules) {
load_grammar(s, n, rules);
}
peg(const char* s, const Rules& rules)
: peg(s, strlen(s), rules) {}
peg(const char* s, size_t n)
: peg(s, n, Rules()) {}
peg(const char* s)
: peg(s, strlen(s), Rules()) {}
operator bool() {
return grammar_ != nullptr;
}
bool load_grammar(const char* s, size_t n, const Rules& rules) {
grammar_ = PEGParser::parse(
s, n, rules,
start_,
[&](const char* s, size_t n, size_t id, const std::string& name) {
if (match_action) match_action(s, n, id, name);
},
log);
return grammar_ != nullptr;
}
bool load_grammar(const char* s, size_t n) {
return load_grammar(s, n, Rules());
}
bool load_grammar(const char* s, const Rules& rules) {
auto n = strlen(s);
return load_grammar(s, n, rules);
}
bool load_grammar(const char* s) {
auto n = strlen(s);
return load_grammar(s, n);
}
bool parse_n(const char* s, size_t n) const {
if (grammar_ != nullptr) {
const auto& rule = (*grammar_)[start_];
auto r = rule.parse(s, n);
output_log(s, n, log, r);
return r.ret && r.len == n;
}
return false;
}
bool parse(const char* s) const {
auto n = strlen(s);
return parse_n(s, n);
}
bool parse_n(const char* s, size_t n, any& dt) const {
if (grammar_ != nullptr) {
const auto& rule = (*grammar_)[start_];
auto r = rule.parse(s, n, dt);
output_log(s, n, log, r);
return r.ret && r.len == n;
}
return false;
}
bool parse(const char* s, any& dt) const {
auto n = strlen(s);
return parse_n(s, n, dt);
}
template <typename T>
bool parse_n(const char* s, size_t n, T& val) const {
if (grammar_ != nullptr) {
const auto& rule = (*grammar_)[start_];
auto r = rule.parse_and_get_value(s, n, val);
output_log(s, n, log, r);
return r.ret && r.len == n;
}
return false;
}
template <typename T>
bool parse(const char* s, T& val) const {
auto n = strlen(s);
return parse_n(s, n, val);
}
template <typename T>
bool parse_n(const char* s, size_t n, any& dt, T& val) const {
if (grammar_ != nullptr) {
const auto& rule = (*grammar_)[start_];
auto r = rule.parse_and_get_value(s, n, dt, val);
output_log(s, n, log, r);
return r.ret && r.len == n;
}
return false;
}
template <typename T>
bool parse(const char* s, any& dt, T& val) const {
auto n = strlen(s);
return parse_n(s, n, dt, val);
}
bool search(const char* s, size_t n, size_t& mpos, size_t& mlen) const {
const auto& rule = (*grammar_)[start_];
if (grammar_ != nullptr) {
size_t pos = 0;
while (pos < n) {
size_t len = n - pos;
auto r = rule.parse(s + pos, len);
if (r.ret) {
mpos = pos;
mlen = len;
return true;
}
pos++;
}
}
mpos = 0;
mlen = 0;
return false;
}
bool search(const char* s, size_t& mpos, size_t& mlen) const {
auto n = strlen(s);
return search(s, n, mpos, mlen);
}
Definition& operator[](const char* s) {
return (*grammar_)[s];
}
void enable_packrat_parsing(bool sw) {
if (grammar_ != nullptr) {
auto& rule = (*grammar_)[start_];
rule.enablePackratParsing = sw;
}
}
struct AstNodeInfo {
const char* name;
int tag; // TODO: It should be calculated at compile-time from 'name' with constexpr hash function.
bool optimize_nodes;
};
peg& enable_ast(bool optimize_nodes, std::initializer_list<AstNodeInfo> list) {
for (const auto& info: list) {
ast_node(info);
}
ast_end(optimize_nodes);
return *this;
}
peg& enable_ast(bool optimize_nodes) {
ast_end(optimize_nodes);
return *this;
}
MatchAction match_action;
Log log;
private:
void output_log(const char* s, size_t n, Log log, const Definition::Result& r) const {
if (log) {
if (!r.ret) {
auto line = line_info(s, r.error_pos);
log(line.first, line.second, r.message.empty() ? "syntax error" : r.message);
} else if (r.len != n) {
auto line = line_info(s, s + r.len);
log(line.first, line.second, "syntax error");
}
}
}
void ast_node(const AstNodeInfo& info) {
auto& rule = (*this)[info.name];
auto is_token = rule.is_token;
rule = [info, is_token](const SemanticValues& sv) {
if (is_token) {
return std::make_shared<Ast>(info.name, info.tag, std::string(sv.s, sv.n));
}
if (info.optimize_nodes && sv.size() == 1) {
std::shared_ptr<Ast> ast = sv[0].get<std::shared_ptr<Ast>>();
return ast;
}
return std::make_shared<Ast>(info.name, info.tag, sv.map<std::shared_ptr<Ast>>());
};
}
void ast_end(bool optimize_nodes) {
for (auto& x: *grammar_) {
const auto& name = x.first;
auto& rule = x.second;
auto& action = rule.actions.front();
if (!action) {
auto is_token = rule.is_token;
action = [=](const SemanticValues& sv) {
if (is_token) {
return std::make_shared<Ast>(name.c_str(), AstDefaultTag, std::string(sv.s, sv.n));
}
if (optimize_nodes && sv.size() == 1) {
std::shared_ptr<Ast> ast = sv[0].get<std::shared_ptr<Ast>>();
return ast;
}
return std::make_shared<Ast>(name.c_str(), AstDefaultTag, sv.map<std::shared_ptr<Ast>>());
};
}
}
}
std::shared_ptr<Grammar> grammar_;
std::string start_;
};
/*-----------------------------------------------------------------------------
* Simple interface
*---------------------------------------------------------------------------*/
struct match
{
struct Item {
const char* s;
size_t n;
size_t id;
std::string name;
size_t length() const { return n; }
std::string str() const { return std::string(s, n); }
};
std::vector<Item> matches;
typedef std::vector<Item>::iterator iterator;
typedef std::vector<Item>::const_iterator const_iterator;
bool empty() const {
return matches.empty();
}
size_t size() const {
return matches.size();
}
size_t length(size_t n = 0) {
return matches[n].length();
}
std::string str(size_t n = 0) const {
return matches[n].str();
}
const Item& operator[](size_t n) const {
return matches[n];
}
iterator begin() {
return matches.begin();
}
iterator end() {
return matches.end();
}
const_iterator begin() const {
return matches.cbegin();
}
const_iterator end() const {
return matches.cend();
}
std::vector<size_t> named_capture(const std::string& name) const {
std::vector<size_t> ret;
for (auto i = 0u; i < matches.size(); i++) {
if (matches[i].name == name) {
ret.push_back(i);
}
}
return ret;
}
std::map<std::string, std::vector<size_t>> named_captures() const {
std::map<std::string, std::vector<size_t>> ret;
for (auto i = 0u; i < matches.size(); i++) {
ret[matches[i].name].push_back(i);
}
return ret;
}
std::vector<size_t> indexed_capture(size_t id) const {
std::vector<size_t> ret;
for (auto i = 0u; i < matches.size(); i++) {
if (matches[i].id == id) {
ret.push_back(i);
}
}
return ret;
}
std::map<size_t, std::vector<size_t>> indexed_captures() const {
std::map<size_t, std::vector<size_t>> ret;
for (auto i = 0u; i < matches.size(); i++) {
ret[matches[i].id].push_back(i);
}
return ret;
}
};
inline bool peg_match(const char* syntax, const char* s, match& m) {
m.matches.clear();
peg pg(syntax);
pg.match_action = [&](const char* s, size_t n, size_t id, const std::string& name) {
m.matches.push_back(match::Item{ s, n, id, name });
};
auto ret = pg.parse(s);
if (ret) {
auto n = strlen(s);
m.matches.insert(m.matches.begin(), match::Item{ s, n, 0, std::string() });
}
return ret;
}
inline bool peg_match(const char* syntax, const char* s) {
peg pg(syntax);
return pg.parse(s);
}
inline bool peg_search(peg& pg, const char* s, size_t n, match& m) {
m.matches.clear();
pg.match_action = [&](const char* s, size_t n, size_t id, const std::string& name) {
m.matches.push_back(match::Item{ s, n, id, name });
};
size_t mpos, mlen;
auto ret = pg.search(s, n, mpos, mlen);
if (ret) {
m.matches.insert(m.matches.begin(), match::Item{ s + mpos, mlen, 0, std::string() });
return true;
}
return false;
}
inline bool peg_search(peg& pg, const char* s, match& m) {
auto n = strlen(s);
return peg_search(pg, s, n, m);
}
inline bool peg_search(const char* syntax, const char* s, size_t n, match& m) {
peg pg(syntax);
return peg_search(pg, s, n, m);
}
inline bool peg_search(const char* syntax, const char* s, match& m) {
peg pg(syntax);
auto n = strlen(s);
return peg_search(pg, s, n, m);
}
class peg_token_iterator : public std::iterator<std::forward_iterator_tag, match>
{
public:
peg_token_iterator()
: s_(nullptr)
, l_(0)
, pos_(std::numeric_limits<size_t>::max()) {}
peg_token_iterator(const char* syntax, const char* s)
: peg_(syntax)
, s_(s)
, l_(strlen(s))
, pos_(0) {
peg_.match_action = [&](const char* s, size_t n, size_t id, const std::string& name) {
m_.matches.push_back(match::Item{ s, n, id, name });
};
search();
}
peg_token_iterator(const peg_token_iterator& rhs)
: peg_(rhs.peg_)
, s_(rhs.s_)
, l_(rhs.l_)
, pos_(rhs.pos_)
, m_(rhs.m_) {}
peg_token_iterator& operator++() {
search();
return *this;
}
peg_token_iterator operator++(int) {
auto it = *this;
search();
return it;
}
match& operator*() {
return m_;
}
match* operator->() {
return &m_;
}
bool operator==(const peg_token_iterator& rhs) {
return pos_ == rhs.pos_;
}
bool operator!=(const peg_token_iterator& rhs) {
return pos_ != rhs.pos_;
}
private:
void search() {
m_.matches.clear();
size_t mpos, mlen;
if (peg_.search(s_ + pos_, l_ - pos_, mpos, mlen)) {
m_.matches.insert(m_.matches.begin(), match::Item{ s_ + mpos, mlen, 0 });
pos_ += mpos + mlen;
} else {
pos_ = std::numeric_limits<size_t>::max();
}
}
peg peg_;
const char* s_;
size_t l_;
size_t pos_;
match m_;
};
struct peg_token_range {
typedef peg_token_iterator iterator;
typedef const peg_token_iterator const_iterator;
peg_token_range(const char* syntax, const char* s)
: beg_iter(peg_token_iterator(syntax, s))
, end_iter() {}
iterator begin() {
return beg_iter;
}
iterator end() {
return end_iter;
}
const_iterator cbegin() const {
return beg_iter;
}
const_iterator cend() const {
return end_iter;
}
private:
peg_token_iterator beg_iter;
peg_token_iterator end_iter;
};
} // namespace peglib
#endif
// vim: et ts=4 sw=4 cin cino={1s ff=unix
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