You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
91 lines
3.3 KiB
91 lines
3.3 KiB
// Copyright 2005-2024 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the 'License');
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an 'AS IS' BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
// See www.openfst.org for extensive documentation on this weighted
|
|
// finite-state transducer library.
|
|
|
|
#ifndef FST_SCRIPT_REPLACE_H_
|
|
#define FST_SCRIPT_REPLACE_H_
|
|
|
|
#include <cstdint>
|
|
#include <tuple>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include <fst/log.h>
|
|
#include <fst/fst.h>
|
|
#include <fst/mutable-fst.h>
|
|
#include <fst/properties.h>
|
|
#include <fst/replace-util.h>
|
|
#include <fst/replace.h>
|
|
#include <fst/util.h>
|
|
#include <fst/script/fst-class.h>
|
|
|
|
namespace fst {
|
|
namespace script {
|
|
|
|
struct ReplaceOptions {
|
|
const int64_t root; // Root rule for expansion.
|
|
const ReplaceLabelType call_label_type; // How to label call arc.
|
|
const ReplaceLabelType return_label_type; // How to label return arc.
|
|
const int64_t return_label; // Specifies return arc label.
|
|
|
|
explicit ReplaceOptions(
|
|
int64_t root, ReplaceLabelType call_label_type = REPLACE_LABEL_INPUT,
|
|
ReplaceLabelType return_label_type = REPLACE_LABEL_NEITHER,
|
|
int64_t return_label = 0)
|
|
: root(root),
|
|
call_label_type(call_label_type),
|
|
return_label_type(return_label_type),
|
|
return_label(return_label) {}
|
|
};
|
|
|
|
using FstReplaceArgs =
|
|
std::tuple<const std::vector<std::pair<int64_t, const FstClass *>> &,
|
|
MutableFstClass *, const ReplaceOptions &>;
|
|
|
|
template <class Arc>
|
|
void Replace(FstReplaceArgs *args) {
|
|
// Now that we know the arc type, we construct a vector of
|
|
// std::pair<real label, real fst> that the real Replace will use.
|
|
const auto &untyped_pairs = std::get<0>(*args);
|
|
std::vector<std::pair<typename Arc::Label, const Fst<Arc> *>> typed_pairs;
|
|
typed_pairs.reserve(untyped_pairs.size());
|
|
for (const auto &untyped_pair : untyped_pairs) {
|
|
typed_pairs.emplace_back(untyped_pair.first, // Converts label.
|
|
untyped_pair.second->GetFst<Arc>());
|
|
}
|
|
MutableFst<Arc> *ofst = std::get<1>(*args)->GetMutableFst<Arc>();
|
|
const auto &opts = std::get<2>(*args);
|
|
ReplaceFstOptions<Arc> typed_opts(opts.root, opts.call_label_type,
|
|
opts.return_label_type, opts.return_label);
|
|
ReplaceFst<Arc> rfst(typed_pairs, typed_opts);
|
|
// Checks for cyclic dependencies before attempting expansion.
|
|
if (rfst.CyclicDependencies()) {
|
|
FSTERROR() << "Replace: Cyclic dependencies detected; cannot expand";
|
|
ofst->SetProperties(kError, kError);
|
|
return;
|
|
}
|
|
typed_opts.gc = true; // Caching options to speed up batch copy.
|
|
typed_opts.gc_limit = 0;
|
|
*ofst = rfst;
|
|
}
|
|
|
|
void Replace(const std::vector<std::pair<int64_t, const FstClass *>> &pairs,
|
|
MutableFstClass *ofst, const ReplaceOptions &opts);
|
|
|
|
} // namespace script
|
|
} // namespace fst
|
|
|
|
#endif // FST_SCRIPT_REPLACE_H_
|