1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef LIBTEXTCLASSIFIER_UTILS_GRAMMAR_SEMANTICS_EVALUATORS_SPAN_EVAL_H_ 18 #define LIBTEXTCLASSIFIER_UTILS_GRAMMAR_SEMANTICS_EVALUATORS_SPAN_EVAL_H_ 19 20 #include "annotator/types.h" 21 #include "utils/base/arena.h" 22 #include "utils/base/statusor.h" 23 #include "utils/grammar/semantics/eval-context.h" 24 #include "utils/grammar/semantics/evaluator.h" 25 #include "utils/grammar/semantics/expression_generated.h" 26 #include "utils/grammar/semantics/value.h" 27 28 namespace libtextclassifier3::grammar { 29 30 // Returns a value lifted from a parse tree. 31 class SpanAsStringEvaluator : public SemanticExpressionEvaluator { 32 public: Apply(const EvalContext & context,const SemanticExpression * expression,UnsafeArena * arena)33 StatusOr<const SemanticValue*> Apply(const EvalContext& context, 34 const SemanticExpression* expression, 35 UnsafeArena* arena) const override { 36 TC3_DCHECK_EQ(expression->expression_type(), 37 SemanticExpression_::Expression_SpanAsStringExpression); 38 return SemanticValue::Create( 39 context.text_context->Span(context.parse_tree->codepoint_span), arena); 40 } 41 }; 42 43 } // namespace libtextclassifier3::grammar 44 45 #endif // LIBTEXTCLASSIFIER_UTILS_GRAMMAR_SEMANTICS_EVALUATORS_SPAN_EVAL_H_ 46