lix/src/libutil/position.hh
eldritch horrors 4c072c7c5f match line endings used by parser and error reports
the parser treats a plain \r as a newline, error reports do not. this
can lead to interesting divergences if anything makes use of this
feature, with error reports pointing to wrong locations in the input (or
even outside the input altogether).

(cherry picked from commit 2be6b143289e5479cc4a2667bb84e879116c2447)
Change-Id: Ieb7f7655bac8cb0cf5734c60bd41723388f2973c
2024-03-18 16:12:46 +01:00

117 lines
3.1 KiB
C++

#pragma once
/**
* @file
*
* @brief Pos and AbstractPos
*/
#include <cstdint>
#include <string>
#include "source-path.hh"
namespace nix {
/**
* A position and an origin for that position (like a source file).
*/
struct Pos
{
uint32_t line = 0;
uint32_t column = 0;
struct Stdin {
ref<std::string> source;
bool operator==(const Stdin & rhs) const
{ return *source == *rhs.source; }
bool operator!=(const Stdin & rhs) const
{ return *source != *rhs.source; }
bool operator<(const Stdin & rhs) const
{ return *source < *rhs.source; }
};
struct String {
ref<std::string> source;
bool operator==(const String & rhs) const
{ return *source == *rhs.source; }
bool operator!=(const String & rhs) const
{ return *source != *rhs.source; }
bool operator<(const String & rhs) const
{ return *source < *rhs.source; }
};
typedef std::variant<std::monostate, Stdin, String, SourcePath> Origin;
Origin origin = std::monostate();
Pos() { }
Pos(uint32_t line, uint32_t column, Origin origin)
: line(line), column(column), origin(origin) { }
Pos(Pos & other) = default;
Pos(const Pos & other) = default;
Pos(Pos && other) = default;
Pos(const Pos * other);
explicit operator bool() const { return line > 0; }
operator std::shared_ptr<Pos>() const;
/**
* Return the contents of the source file.
*/
std::optional<std::string> getSource() const;
void print(std::ostream & out, bool showOrigin) const;
std::optional<LinesOfCode> getCodeLines() const;
bool operator==(const Pos & rhs) const = default;
bool operator!=(const Pos & rhs) const = default;
bool operator<(const Pos & rhs) const;
struct LinesIterator {
using difference_type = size_t;
using value_type = std::string_view;
using reference = const std::string_view &;
using pointer = const std::string_view *;
using iterator_category = std::input_iterator_tag;
LinesIterator(): pastEnd(true) {}
explicit LinesIterator(std::string_view input): input(input), pastEnd(input.empty()) {
if (!pastEnd)
bump(true);
}
LinesIterator & operator++() {
bump(false);
return *this;
}
LinesIterator operator++(int) {
auto result = *this;
++*this;
return result;
}
reference operator*() const { return curLine; }
pointer operator->() const { return &curLine; }
bool operator!=(const LinesIterator & other) const {
return !(*this == other);
}
bool operator==(const LinesIterator & other) const {
return (pastEnd && other.pastEnd)
|| (std::forward_as_tuple(input.size(), input.data())
== std::forward_as_tuple(other.input.size(), other.input.data()));
}
private:
std::string_view input, curLine;
bool pastEnd = false;
void bump(bool atFirst);
};
};
std::ostream & operator<<(std::ostream & str, const Pos & pos);
}