84 lines
2.5 KiB
C++
84 lines
2.5 KiB
C++
/** @file SchematikaReader.hpp
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*
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* @author Roland Conybeare, Jan 2026
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**/
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#pragma once
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#include "ReaderConfig.hpp"
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#include "SchematikaParser.hpp"
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#include <xo/tokenizer2/Tokenizer.hpp>
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namespace xo {
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namespace scm {
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struct ReaderResult {
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using span_type = xo::mm::span<const char>;
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bool is_tk_error() const { return tk_error_.is_error(); }
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/** schematika expression parsed from input **/
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obj<AExpression> expr_;
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/** unconsumed portion of input span
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* only relevant when result type is expression.
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* (otherwise input consumed)
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**/
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span_type remaining_input_;
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/** {src_function, error_description, input_state, error_pos} **/
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TokenizerError tk_error_;
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};
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/** @class SchematikaReader
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* @brief Pipeline comprising Schematika tokenizer and parser
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*
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* Consumes text; produces expressions
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**/
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class SchematikaReader {
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public:
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using AAllocator = xo::mm::AAllocator;
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using span_type = xo::mm::span<const char>;
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using size_type = std::size_t;
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public:
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SchematikaReader(const ReaderConfig & config,
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obj<AAllocator> expr_alloc);
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/** true iff parser is at top-level.
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* false iff parser is working on incomplete expression
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**/
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bool is_at_toplevel() const noexcept;
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/** prepare interactive session
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* (allows rvalue expressions at toplevel)
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**/
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void begin_interactive_session();
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/** consume input @p input_cstr **/
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const ReaderResult & read_expr(span_type input_span, bool eof);
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/** reset to known starting point after encountering an error.
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* - remainder of stashed current line.
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* Necesary for well-formatted error reporting.
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* - current parsing state
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**/
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void reset_to_idle_toplevel();
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private:
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/** tokenizer converts a stream of chars
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* to a stream of lexical tokens
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**/
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Tokenizer tokenizer_;
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/** parser converts a stream of tokens
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* to a stream of expressions
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**/
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SchematikaParser parser_;
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/** current output from reader **/
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ReaderResult result_;
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};
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} /*namespace scm*/
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} /*namespace xo*/
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/* end SchematikaReader.hpp */
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