nixpkgs/pkgs/tools/nix/nixos-option/libnix-copy-paste.cc
2021-07-09 08:59:12 +02:00

83 lines
2.6 KiB
C++

// These are useful methods inside the nix library that ought to be exported.
// Since they are not, copy/paste them here.
// TODO: Delete these and use the ones in the library as they become available.
#include <nix/config.h> // for nix/globals.hh's reference to SYSTEM
#include "libnix-copy-paste.hh"
#include <boost/format/alt_sstream.hpp> // for basic_altstringbuf...
#include <boost/format/alt_sstream_impl.hpp> // for basic_altstringbuf...
#include <boost/format/format_class.hpp> // for basic_format
#include <boost/format/format_fwd.hpp> // for format
#include <boost/format/format_implementation.hpp> // for basic_format::basi...
#include <boost/optional/optional.hpp> // for get_pointer
#include <iostream> // for operator<<, basic_...
#include <nix/types.hh> // for Strings, Error
#include <string> // for string, basic_string
using boost::format;
using nix::Error;
using nix::Strings;
using std::string;
// From nix/src/libexpr/attr-path.cc
Strings parseAttrPath(const string & s)
{
Strings res;
string cur;
string::const_iterator i = s.begin();
while (i != s.end()) {
if (*i == '.') {
res.push_back(cur);
cur.clear();
} else if (*i == '"') {
++i;
while (1) {
if (i == s.end())
throw Error(format("missing closing quote in selection path '%1%'") % s);
if (*i == '"')
break;
cur.push_back(*i++);
}
} else
cur.push_back(*i);
++i;
}
if (!cur.empty())
res.push_back(cur);
return res;
}
// From nix/src/nix/repl.cc
bool isVarName(const string & s)
{
if (s.size() == 0)
return false;
char c = s[0];
if ((c >= '0' && c <= '9') || c == '-' || c == '\'')
return false;
for (auto & i : s)
if (!((i >= 'a' && i <= 'z') || (i >= 'A' && i <= 'Z') || (i >= '0' && i <= '9') || i == '_' || i == '-' ||
i == '\''))
return false;
return true;
}
// From nix/src/nix/repl.cc
std::ostream & printStringValue(std::ostream & str, const char * string)
{
str << "\"";
for (const char * i = string; *i; i++)
if (*i == '\"' || *i == '\\')
str << "\\" << *i;
else if (*i == '\n')
str << "\\n";
else if (*i == '\r')
str << "\\r";
else if (*i == '\t')
str << "\\t";
else
str << *i;
str << "\"";
return str;
}