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ledger/src/commodity.cc
John Wiegley 653d2bd99a Corrected a verification test
2010-06-05 02:18:01 -04:00

786 lines
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/*
* Copyright (c) 2003-2010, John Wiegley. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of New Artisans LLC nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <system.hh>
#include "amount.h"
#include "commodity.h"
#include "annotate.h"
#include "pool.h"
namespace ledger {
bool commodity_t::decimal_comma_by_default = false;
void commodity_t::history_t::add_price(commodity_t& source,
const datetime_t& date,
const amount_t& price,
const bool reflexive)
{
DEBUG("commodity.prices.add", "add_price to " << source
<< (reflexive ? " (secondary)" : " (primary)")
<< " : " << date << ", " << price);
history_map::iterator i = prices.find(date);
if (i != prices.end()) {
(*i).second = price;
} else {
std::pair<history_map::iterator, bool> result
= prices.insert(history_map::value_type(date, price));
assert(result.second);
}
if (reflexive) {
amount_t inverse = price.inverted();
inverse.set_commodity(const_cast<commodity_t&>(source));
price.commodity().add_price(date, inverse, false);
} else {
DEBUG("commodity.prices.add",
"marking commodity " << source.symbol() << " as primary");
source.add_flags(COMMODITY_PRIMARY);
}
}
bool commodity_t::history_t::remove_price(const datetime_t& date)
{
DEBUG("commodity.prices.add", "remove_price: " << date);
history_map::size_type n = prices.erase(date);
if (n > 0)
return true;
return false;
}
void commodity_t::varied_history_t::
add_price(commodity_t& source,
const datetime_t& date,
const amount_t& price,
const bool reflexive)
{
optional<history_t&> hist = history(price.commodity());
if (! hist) {
std::pair<history_by_commodity_map::iterator, bool> result
= histories.insert(history_by_commodity_map::value_type
(&price.commodity(), history_t()));
assert(result.second);
hist = (*result.first).second;
}
assert(hist);
hist->add_price(source, date, price, reflexive);
}
bool commodity_t::varied_history_t::remove_price(const datetime_t& date,
commodity_t& comm)
{
DEBUG("commodity.prices.add", "varied_remove_price: " << date << ", " << comm);
if (optional<history_t&> hist = history(comm))
return hist->remove_price(date);
return false;
}
optional<price_point_t>
commodity_t::history_t::find_price(const optional<datetime_t>& moment,
const optional<datetime_t>& oldest
#if defined(DEBUG_ON)
, const int indent
#endif
) const
{
price_point_t point;
bool found = false;
#if defined(DEBUG_ON)
#define DEBUG_INDENT(cat, indent) \
do { \
if (SHOW_DEBUG(cat)) \
for (int i = 0; i < indent; i++) \
ledger::_log_buffer << " "; \
} while (false)
#else
#define DEBUG_INDENT(cat, indent)
#endif
#if defined(DEBUG_ON)
DEBUG_INDENT("commodity.prices.find", indent);
if (moment)
DEBUG("commodity.prices.find", "find price nearest before or on: " << *moment);
else
DEBUG("commodity.prices.find", "find any price");
if (oldest) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "but no older than: " << *oldest);
}
#endif
if (prices.size() == 0) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "there are no prices in this history");
return none;
}
if (! moment) {
history_map::const_reverse_iterator r = prices.rbegin();
point.when = (*r).first;
point.price = (*r).second;
found = true;
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "using most recent price");
} else {
history_map::const_iterator i = prices.upper_bound(*moment);
if (i == prices.end()) {
history_map::const_reverse_iterator r = prices.rbegin();
point.when = (*r).first;
point.price = (*r).second;
found = true;
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "using last price");
} else {
point.when = (*i).first;
if (*moment < point.when) {
if (i != prices.begin()) {
--i;
point.when = (*i).first;
point.price = (*i).second;
found = true;
}
} else {
point.price = (*i).second;
found = true;
}
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "using found price");
}
}
if (! found) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "could not find a price");
return none;
}
else if (moment && point.when > *moment) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "price is too young ");
return none;
}
else if (oldest && point.when < *oldest) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "price is too old ");
return none;
}
else {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find",
"returning price: " << point.when << ", " << point.price);
return point;
}
}
optional<price_point_t>
commodity_t::varied_history_t::find_price(const commodity_t& source,
const optional<commodity_t&>& commodity,
const optional<datetime_t>& moment,
const optional<datetime_t>& oldest
#if defined(DEBUG_ON)
, const int indent
#endif
) const
{
optional<price_point_t> point;
optional<datetime_t> limit = oldest;
#if defined(VERIFY_ON)
if (commodity) {
VERIFY(source != *commodity);
VERIFY(! commodity->has_annotation());
VERIFY(source.referent() != commodity->referent());
}
#endif
#if defined(DEBUG_ON)
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "varied_find_price for: " << source);
DEBUG_INDENT("commodity.prices.find", indent);
if (commodity)
DEBUG("commodity.prices.find", "looking for: commodity '" << *commodity << "'");
else
DEBUG("commodity.prices.find", "looking for: any commodity");
if (moment) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "time index: " << *moment);
}
if (oldest) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "only consider prices younger than: " << *oldest);
}
#endif
// Either we couldn't find a history for the target commodity, or we
// couldn't find a price. In either case, search all histories known
// to this commodity for a price which we can calculate in terms of
// the goal commodity.
price_point_t best;
bool found = false;
foreach (const history_by_commodity_map::value_type& hist, histories) {
commodity_t& comm(*hist.first);
if (comm == source)
continue;
// Only value secondary commodities in terms of primary ones
if (! commodity && ! comm.has_flags(COMMODITY_PRIMARY))
continue;
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find",
"searching for price via commodity '" << comm << "'");
point = hist.second.find_price(moment, limit
#if defined(DEBUG_ON)
, indent + 2
#endif
);
assert(! point || point->price.commodity() == comm);
if (point) {
optional<price_point_t> xlat;
if (commodity && comm != *commodity) {
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find", "looking for translation price");
xlat = comm.find_price(commodity, moment, limit, true
#if defined(DEBUG_ON)
, indent + 2
#endif
);
if (xlat) {
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find", "found translated price "
<< xlat->price << " from " << xlat->when);
point->price = xlat->price * point->price;
if (xlat->when < point->when) {
point->when = xlat->when;
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find",
"adjusting date of result back to " << point->when);
}
} else {
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find", "saw no translated price there");
continue;
}
}
assert(! commodity || point->price.commodity() == *commodity);
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find",
"saw a price there: " << point->price << " from " << point->when);
if (! limit || point->when > *limit) {
limit = point->when;
best = *point;
found = true;
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find",
"search limit adjusted to " << *limit);
}
} else {
DEBUG_INDENT("commodity.prices.find", indent + 1);
DEBUG("commodity.prices.find", "saw no price there");
}
}
if (found) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.download",
"found price " << best.price << " from " << best.when);
return best;
}
return none;
}
optional<commodity_t::history_t&>
commodity_t::varied_history_t::history(const optional<commodity_t&>& commodity)
{
commodity_t * comm = NULL;
if (! commodity) {
if (histories.size() > 1)
return none;
comm = (*histories.begin()).first;
} else {
comm = &(*commodity);
}
history_by_commodity_map::iterator i = histories.find(comm);
if (i != histories.end())
return (*i).second;
return none;
}
optional<price_point_t>
commodity_t::find_price(const optional<commodity_t&>& commodity,
const optional<datetime_t>& moment,
const optional<datetime_t>& oldest,
const bool nested
#if defined(DEBUG_ON)
, const int indent
#endif
) const
{
if (! has_flags(COMMODITY_WALKED) && base->varied_history &&
(commodity || ! has_flags(COMMODITY_PRIMARY))) {
optional<base_t::time_and_commodity_t> pair;
#if defined(VERIFY_ON)
optional<price_point_t> checkpoint;
bool found = false;
#endif
if (! nested) {
pair = base_t::time_and_commodity_t
(base_t::optional_time_pair_t(moment, oldest),
commodity ? &(*commodity) : NULL);
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "looking for memoized args: "
<< (moment ? format_datetime(*moment) : "NONE") << ", "
<< (oldest ? format_datetime(*oldest) : "NONE") << ", "
<< (commodity ? commodity->symbol() : "NONE"));
base_t::memoized_price_map::iterator i = base->price_map.find(*pair);
if (i != base->price_map.end()) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "found! returning: "
<< ((*i).second ? (*i).second->price : amount_t(0L)));
#if defined(VERIFY_ON)
IF_VERIFY() {
found = true;
checkpoint = (*i).second;
} else
#endif // defined(VERIFY_ON)
return (*i).second;
}
}
optional<price_point_t> point;
const_cast<commodity_t&>(*this).add_flags(COMMODITY_WALKED);
try {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find", "manually finding price...");
point = base->varied_history->find_price(*this, commodity,
moment, oldest
#if defined(DEBUG_ON)
, indent
#endif
);
}
catch (...) {
const_cast<commodity_t&>(*this).drop_flags(COMMODITY_WALKED);
throw;
}
const_cast<commodity_t&>(*this).drop_flags(COMMODITY_WALKED);
#if defined(VERIFY_ON)
if (DO_VERIFY() && found) {
VERIFY(checkpoint == point);
return checkpoint;
}
#endif // defined(VERIFY_ON)
if (! nested && pair) {
if (base->price_map.size() > base_t::max_price_map_size) {
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find",
"price map has grown too large, clearing it by half");
for (std::size_t i = 0; i < base_t::max_price_map_size >> 1; i++)
base->price_map.erase(base->price_map.begin());
}
DEBUG_INDENT("commodity.prices.find", indent);
DEBUG("commodity.prices.find",
"remembered: " << (point ? point->price : amount_t(0L)));
base->price_map.insert
(base_t::memoized_price_map::value_type(*pair, point));
}
return point;
}
return none;
}
optional<price_point_t>
commodity_t::check_for_updated_price(const optional<price_point_t>& point,
const optional<datetime_t>& moment,
const optional<commodity_t&>& in_terms_of)
{
if (pool().get_quotes && ! has_flags(COMMODITY_NOMARKET)) {
bool exceeds_leeway = true;
if (point) {
time_duration_t::sec_type seconds_diff;
if (moment) {
seconds_diff = (*moment - point->when).total_seconds();
DEBUG("commodity.download", "moment = " << *moment);
DEBUG("commodity.download", "slip.moment = " << seconds_diff);
} else {
seconds_diff = (TRUE_CURRENT_TIME() - point->when).total_seconds();
DEBUG("commodity.download", "slip.now = " << seconds_diff);
}
DEBUG("commodity.download", "leeway = " << pool().quote_leeway);
if (seconds_diff < pool().quote_leeway)
exceeds_leeway = false;
}
if (exceeds_leeway) {
DEBUG("commodity.download",
"attempting to download a more current quote...");
if (optional<price_point_t> quote =
pool().get_commodity_quote(*this, in_terms_of)) {
if (! in_terms_of ||
(quote->price.has_commodity() &&
quote->price.commodity() == *in_terms_of))
return quote;
}
}
}
return point;
}
commodity_t::operator bool() const
{
return this != pool().null_commodity;
}
bool commodity_t::symbol_needs_quotes(const string& symbol)
{
foreach (char ch, symbol)
if (std::isspace(ch) || std::isdigit(ch) || ch == '-' || ch == '.')
return true;
return false;
}
namespace {
bool is_reserved_token(const char * buf)
{
switch (buf[0]) {
case 'a':
return std::strcmp(buf, "and") == 0;
case 'd':
return std::strcmp(buf, "div") == 0;
case 'e':
return std::strcmp(buf, "else") == 0;
case 'f':
return std::strcmp(buf, "false") == 0;
case 'i':
return std::strcmp(buf, "if") == 0;
case 'o':
return std::strcmp(buf, "or") == 0;
case 'n':
return std::strcmp(buf, "not") == 0;
case 't':
return std::strcmp(buf, "true") == 0;
}
return false;
}
}
void commodity_t::parse_symbol(std::istream& in, string& symbol)
{
// Invalid commodity characters:
// SPACE, TAB, NEWLINE, RETURN
// 0-9 . , ; : ? ! - + * / ^ & | =
// < > { } [ ] ( ) @
static int invalid_chars[256] = {
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
/* 00 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0,
/* 10 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 20 */ 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1,
/* 30 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
/* 40 */ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 50 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0,
/* 60 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 70 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1,
/* 80 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 90 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* a0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* b0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* c0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* d0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* e0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* f0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
istream_pos_type pos = in.tellg();
char buf[256];
char c = peek_next_nonws(in);
if (c == '"') {
in.get(c);
READ_INTO(in, buf, 255, c, c != '"');
if (c == '"')
in.get(c);
else
throw_(amount_error, _("Quoted commodity symbol lacks closing quote"));
} else {
char * _p = buf;
c = static_cast<char>(in.peek());
while (_p - buf < 255 && in.good() && ! in.eof() && c != '\n') {
std::size_t bytes = 0;
std::ptrdiff_t size = _p - buf;
unsigned char d = c;
// Check for the start of a UTF-8 multi-byte encoded string
if (d >= 192 && d <= 223 && size < 254)
bytes = 2;
else if (d >= 224 && d <= 239 && size < 253)
bytes = 3;
else if (d >= 240 && d <= 247 && size < 252)
bytes = 4;
else if (d >= 248 && d <= 251 && size < 251)
bytes = 5;
else if (d >= 252 && d <= 253 && size < 250)
bytes = 6;
else if (d >= 254) // UTF-8 encoding error
break;
if (bytes > 0) { // we're looking at a UTF-8 encoding
for (std::size_t i = 0; i < bytes; i++) {
in.get(c);
if (in.bad() || in.eof())
throw_(amount_error, _("Invalid UTF-8 encoding for commodity name"));
*_p++ = c;
}
}
else if (invalid_chars[static_cast<unsigned char>(c)]) {
break;
}
else {
in.get(c);
if (in.eof())
break;
if (c == '\\') {
in.get(c);
if (in.eof())
throw_(amount_error, _("Backslash at end of commodity name"));
}
*_p++ = c;
}
c = static_cast<char>(in.peek());
}
*_p = '\0';
if (is_reserved_token(buf))
buf[0] = '\0';
}
symbol = buf;
if (symbol.length() == 0) {
in.clear();
in.seekg(pos, std::ios::beg);
}
}
void commodity_t::parse_symbol(char *& p, string& symbol)
{
if (*p == '"') {
char * q = std::strchr(p + 1, '"');
if (! q)
throw_(amount_error, _("Quoted commodity symbol lacks closing quote"));
symbol = string(p + 1, 0, q - p - 1);
p = q + 2;
} else {
char * q = next_element(p);
symbol = p;
if (q)
p = q;
else
p += symbol.length();
}
if (symbol.empty())
throw_(amount_error, _("Failed to parse commodity"));
}
bool commodity_t::valid() const
{
if (symbol().empty() && this != pool().null_commodity) {
DEBUG("ledger.validate",
"commodity_t: symbol().empty() && this != null_commodity");
return false;
}
if (annotated && ! base) {
DEBUG("ledger.validate", "commodity_t: annotated && ! base");
return false;
}
if (precision() > 16) {
DEBUG("ledger.validate", "commodity_t: precision() > 16");
return false;
}
return true;
}
bool commodity_t::compare_by_commodity::operator()(const amount_t * left,
const amount_t * right) const
{
commodity_t& leftcomm(left->commodity());
commodity_t& rightcomm(right->commodity());
DEBUG("commodity.compare", " left symbol (" << leftcomm << ")");
DEBUG("commodity.compare", "right symbol (" << rightcomm << ")");
int cmp = leftcomm.base_symbol().compare(rightcomm.base_symbol());
if (cmp != 0)
return cmp < 0;
if (! leftcomm.has_annotation()) {
return rightcomm.has_annotation();
}
else if (! rightcomm.has_annotation()) {
return ! leftcomm.has_annotation();
}
else {
annotated_commodity_t& aleftcomm(static_cast<annotated_commodity_t&>(leftcomm));
annotated_commodity_t& arightcomm(static_cast<annotated_commodity_t&>(rightcomm));
if (! aleftcomm.details.price && arightcomm.details.price)
return true;
if (aleftcomm.details.price && ! arightcomm.details.price)
return false;
if (aleftcomm.details.price && arightcomm.details.price) {
amount_t leftprice(*aleftcomm.details.price);
amount_t rightprice(*arightcomm.details.price);
if (leftprice.commodity() == rightprice.commodity()) {
return (leftprice - rightprice).sign() < 0;
} else {
// Since we have two different amounts, there's really no way
// to establish a true sorting order; we'll just do it based
// on the numerical values.
leftprice.clear_commodity();
rightprice.clear_commodity();
return (leftprice - rightprice).sign() < 0;
}
}
if (! aleftcomm.details.date && arightcomm.details.date)
return true;
if (aleftcomm.details.date && ! arightcomm.details.date)
return false;
if (aleftcomm.details.date && arightcomm.details.date) {
gregorian::date_duration diff =
*aleftcomm.details.date - *arightcomm.details.date;
return diff.is_negative();
}
if (! aleftcomm.details.tag && arightcomm.details.tag)
return true;
if (aleftcomm.details.tag && ! arightcomm.details.tag)
return false;
if (aleftcomm.details.tag && arightcomm.details.tag)
return *aleftcomm.details.tag < *arightcomm.details.tag;
assert(false);
return true;
}
}
void to_xml(std::ostream& out, const commodity_t& comm,
bool commodity_details)
{
push_xml x(out, "commodity", true);
out << " flags=\"";
if (! (comm.has_flags(COMMODITY_STYLE_SUFFIXED))) out << 'P';
if (comm.has_flags(COMMODITY_STYLE_SEPARATED)) out << 'S';
if (comm.has_flags(COMMODITY_STYLE_THOUSANDS)) out << 'T';
if (comm.has_flags(COMMODITY_STYLE_DECIMAL_COMMA)) out << 'D';
out << '"';
x.close_attrs();
{
push_xml y(out, "symbol");
out << y.guard(comm.symbol());
}
if (commodity_details) {
if (comm.has_annotation())
to_xml(out, as_annotated_commodity(comm).details);
if (comm.varied_history()) {
push_xml y(out, "varied-history");
foreach (const commodity_t::history_by_commodity_map::value_type& pair,
comm.varied_history()->histories) {
{
push_xml z(out, "symbol");
out << y.guard(pair.first->symbol());
}
{
push_xml z(out, "history");
foreach (const commodity_t::history_map::value_type& inner_pair,
pair.second.prices) {
push_xml w(out, "price-point");
to_xml(out, inner_pair.first);
to_xml(out, inner_pair.second);
}
}
}
}
}
}
} // namespace ledger
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