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