nix/src/libutil/error.hh

#pragma once

#include "types.hh"
#include <string>
#include <optional>

using std::string;
using std::optional;

namespace nix {

enum ErrLevel 
  { elWarning
  , elError
  };

class ColumnRange { 
  public:
  unsigned int start;
  unsigned int len;
};

class ErrLine { 
  public:
  int lineNumber;
  optional<ColumnRange> columnRange;
  optional<string> prevLineOfCode;
  string errLineOfCode;
  optional<string> nextLineOfCode;
};

class NixCode { 
  public:
  optional<string> nixFile;
  optional<ErrLine> errLine;
};


class ErrorInfo { 
  public:
  ErrLevel level;
  string name;
  string description;
  string program;
  optional<NixCode> nixCode;
  string hint;
  ErrorInfo& GetEI() { return *this; }
};

template <class T>
class AddName : private T
{
  public:
    T& name(const std::string &name){
      GetEI().name = name;
      return *this;
    }
  protected:
    ErrorInfo& GetEI() { return T::GetEI(); }
};

template <class T>
class AddDescription : private T 
{
  public:
    T& description(const std::string &description){
      GetEI().description = description;
      return *this;
    }
  protected:
    ErrorInfo& GetEI() { return T::GetEI(); }
};

typedef AddName<AddDescription<ErrorInfo>> StandardError;

string showErrLine(ErrLine &errLine);

void print_code_lines(string &prefix, NixCode &nix_code); 

void print_error(ErrorInfo &einfo);
}