forked from lix-project/lix
74 lines
1.8 KiB
C++
74 lines
1.8 KiB
C++
#include "command.hh"
|
|
#include "common-args.hh"
|
|
#include "shared.hh"
|
|
#include "store-api.hh"
|
|
#include "eval.hh"
|
|
#include "json.hh"
|
|
#include "value-to-json.hh"
|
|
#include "progress-bar.hh"
|
|
|
|
using namespace nix;
|
|
|
|
struct CmdEval : MixJSON, InstallableCommand
|
|
{
|
|
bool raw = false;
|
|
|
|
CmdEval()
|
|
{
|
|
mkFlag(0, "raw", "print strings unquoted", &raw);
|
|
}
|
|
|
|
std::string description() override
|
|
{
|
|
return "evaluate a Nix expression";
|
|
}
|
|
|
|
Examples examples() override
|
|
{
|
|
return {
|
|
Example{
|
|
"To evaluate a Nix expression given on the command line:",
|
|
"nix eval '(1 + 2)'"
|
|
},
|
|
Example{
|
|
"To evaluate a Nix expression from a file or URI:",
|
|
"nix eval -f channel:nixos-17.09 hello.name"
|
|
},
|
|
Example{
|
|
"To get the current version of Nixpkgs:",
|
|
"nix eval --raw nixpkgs.lib.version"
|
|
},
|
|
Example{
|
|
"To print the store path of the Hello package:",
|
|
"nix eval --raw nixpkgs.hello"
|
|
},
|
|
};
|
|
}
|
|
|
|
Category category() override { return catSecondary; }
|
|
|
|
void run(ref<Store> store) override
|
|
{
|
|
if (raw && json)
|
|
throw UsageError("--raw and --json are mutually exclusive");
|
|
|
|
auto state = getEvalState();
|
|
|
|
auto v = installable->toValue(*state).first;
|
|
PathSet context;
|
|
|
|
if (raw) {
|
|
stopProgressBar();
|
|
std::cout << state->coerceToString(noPos, *v, context);
|
|
} else if (json) {
|
|
JSONPlaceholder jsonOut(std::cout);
|
|
printValueAsJSON(*state, true, *v, jsonOut, context);
|
|
} else {
|
|
state->forceValueDeep(*v);
|
|
logger->stdout_("%s", *v);
|
|
}
|
|
}
|
|
};
|
|
|
|
static auto r1 = registerCommand<CmdEval>("eval");
|