644 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			644 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
#include <nix/config.h> // for nix/globals.hh's reference to SYSTEM
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#include <exception>               // for exception_ptr, current_exception
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#include <functional>              // for function
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#include <iostream>                // for operator<<, basic_ostream, ostrin...
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#include <iterator>                // for next
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#include <list>                    // for _List_iterator
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#include <memory>                  // for allocator, unique_ptr, make_unique
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#include <new>                     // for operator new
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#include <nix/args.hh>             // for argvToStrings, UsageError
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#include <nix/attr-path.hh>        // for findAlongAttrPath
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#include <nix/attr-set.hh>         // for Attr, Bindings, Bindings::iterator
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#include <nix/common-eval-args.hh> // for MixEvalArgs
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#include <nix/eval-inline.hh>      // for EvalState::forceValue
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#include <nix/eval.hh>             // for EvalState, initGC, operator<<
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#include <nix/globals.hh>          // for initPlugins, Settings, settings
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#include <nix/nixexpr.hh>          // for Pos
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#include <nix/shared.hh>           // for getArg, LegacyArgs, printVersion
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#include <nix/store-api.hh>        // for openStore
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#include <nix/symbol-table.hh>     // for Symbol, SymbolTable
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#include <nix/types.hh>            // for Error, Path, Strings, PathSet
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#include <nix/util.hh>             // for absPath, baseNameOf
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#include <nix/value.hh>            // for Value, Value::(anonymous), Value:...
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#include <string>                  // for string, operator+, operator==
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#include <utility>                 // for move
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#include <variant>                 // for get, holds_alternative, variant
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#include <vector>                  // for vector<>::iterator, vector
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#include "libnix-copy-paste.hh"
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using nix::absPath;
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using nix::Bindings;
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using nix::Error;
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using nix::EvalError;
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using nix::EvalState;
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using nix::Path;
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using nix::PathSet;
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using nix::Strings;
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using nix::Symbol;
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using nix::tAttrs;
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using nix::ThrownError;
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using nix::tLambda;
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using nix::tString;
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using nix::UsageError;
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using nix::Value;
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// An ostream wrapper to handle nested indentation
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class Out
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{
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  public:
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    class Separator
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    {};
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    const static Separator sep;
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    enum LinePolicy
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    {
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        ONE_LINE,
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        MULTI_LINE
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    };
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    explicit Out(std::ostream & ostream) : ostream(ostream), policy(ONE_LINE), writeSinceSep(true) {}
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    Out(Out & o, const std::string & start, const std::string & end, LinePolicy policy);
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    Out(Out & o, const std::string & start, const std::string & end, int count)
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        : Out(o, start, end, count < 2 ? ONE_LINE : MULTI_LINE)
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    {}
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    Out(const Out &) = delete;
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    Out(Out &&) = default;
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    Out & operator=(const Out &) = delete;
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    Out & operator=(Out &&) = delete;
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    ~Out() { ostream << end; }
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  private:
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    std::ostream & ostream;
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    std::string indentation;
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    std::string end;
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    LinePolicy policy;
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    bool writeSinceSep;
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    template <typename T> friend Out & operator<<(Out & o, T thing);
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};
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template <typename T> Out & operator<<(Out & o, T thing)
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{
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    if (!o.writeSinceSep && o.policy == Out::MULTI_LINE) {
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        o.ostream << o.indentation;
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    }
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    o.writeSinceSep = true;
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    o.ostream << thing;
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    return o;
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}
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template <> Out & operator<<<Out::Separator>(Out & o, Out::Separator /* thing */)
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{
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    o.ostream << (o.policy == Out::ONE_LINE ? " " : "\n");
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    o.writeSinceSep = false;
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    return o;
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}
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Out::Out(Out & o, const std::string & start, const std::string & end, LinePolicy policy)
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    : ostream(o.ostream), indentation(policy == ONE_LINE ? o.indentation : o.indentation + "  "),
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      end(policy == ONE_LINE ? end : o.indentation + end), policy(policy), writeSinceSep(true)
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{
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    o << start;
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    *this << Out::sep;
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}
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// Stuff needed for evaluation
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struct Context
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{
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    Context(EvalState & state, Bindings & autoArgs, Value optionsRoot, Value configRoot)
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        : state(state), autoArgs(autoArgs), optionsRoot(optionsRoot), configRoot(configRoot),
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          underscoreType(state.symbols.create("_type"))
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    {}
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    EvalState & state;
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    Bindings & autoArgs;
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    Value optionsRoot;
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    Value configRoot;
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    Symbol underscoreType;
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};
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Value evaluateValue(Context & ctx, Value & v)
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{
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    ctx.state.forceValue(v);
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    if (ctx.autoArgs.empty()) {
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        return v;
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    }
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    Value called{};
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    ctx.state.autoCallFunction(ctx.autoArgs, v, called);
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    return called;
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}
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bool isOption(Context & ctx, const Value & v)
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{
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    if (v.type != tAttrs) {
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        return false;
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    }
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    const auto & actualType = v.attrs->find(ctx.underscoreType);
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    if (actualType == v.attrs->end()) {
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        return false;
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    }
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    try {
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        Value evaluatedType = evaluateValue(ctx, *actualType->value);
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        if (evaluatedType.type != tString) {
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            return false;
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        }
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        return static_cast<std::string>(evaluatedType.string.s) == "option";
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    } catch (Error &) {
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        return false;
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    }
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}
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// Add quotes to a component of a path.
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// These are needed for paths like:
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//    fileSystems."/".fsType
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//    systemd.units."dbus.service".text
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std::string quoteAttribute(const std::string & attribute)
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{
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    if (isVarName(attribute)) {
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        return attribute;
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    }
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    std::ostringstream buf;
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    printStringValue(buf, attribute.c_str());
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    return buf.str();
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}
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const std::string appendPath(const std::string & prefix, const std::string & suffix)
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{
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    if (prefix.empty()) {
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        return quoteAttribute(suffix);
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    }
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    return prefix + "." + quoteAttribute(suffix);
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}
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bool forbiddenRecursionName(std::string name) { return (!name.empty() && name[0] == '_') || name == "haskellPackages"; }
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void recurse(const std::function<bool(const std::string & path, std::variant<Value, std::exception_ptr>)> & f,
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             Context & ctx, Value v, const std::string & path)
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{
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    std::variant<Value, std::exception_ptr> evaluated;
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    try {
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        evaluated = evaluateValue(ctx, v);
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    } catch (Error &) {
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        evaluated = std::current_exception();
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    }
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    if (!f(path, evaluated)) {
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        return;
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    }
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    if (std::holds_alternative<std::exception_ptr>(evaluated)) {
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        return;
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    }
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    const Value & evaluated_value = std::get<Value>(evaluated);
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    if (evaluated_value.type != tAttrs) {
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        return;
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    }
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    for (const auto & child : evaluated_value.attrs->lexicographicOrder()) {
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        if (forbiddenRecursionName(child->name)) {
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            continue;
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        }
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        recurse(f, ctx, *child->value, appendPath(path, child->name));
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    }
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}
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bool optionTypeIs(Context & ctx, Value & v, const std::string & soughtType)
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{
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    try {
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        const auto & typeLookup = v.attrs->find(ctx.state.sType);
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        if (typeLookup == v.attrs->end()) {
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            return false;
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        }
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        Value type = evaluateValue(ctx, *typeLookup->value);
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        if (type.type != tAttrs) {
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            return false;
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        }
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        const auto & nameLookup = type.attrs->find(ctx.state.sName);
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        if (nameLookup == type.attrs->end()) {
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            return false;
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        }
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        Value name = evaluateValue(ctx, *nameLookup->value);
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        if (name.type != tString) {
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            return false;
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        }
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        return name.string.s == soughtType;
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    } catch (Error &) {
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        return false;
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    }
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}
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bool isAggregateOptionType(Context & ctx, Value & v)
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{
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    return optionTypeIs(ctx, v, "attrsOf") || optionTypeIs(ctx, v, "listOf");
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}
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MakeError(OptionPathError, EvalError);
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Value getSubOptions(Context & ctx, Value & option)
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{
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    Value getSubOptions = evaluateValue(ctx, *findAlongAttrPath(ctx.state, "type.getSubOptions", ctx.autoArgs, option));
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    if (getSubOptions.type != tLambda) {
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        throw OptionPathError("Option's type.getSubOptions isn't a function");
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    }
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    Value emptyString{};
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    nix::mkString(emptyString, "");
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    Value v;
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    ctx.state.callFunction(getSubOptions, emptyString, v, nix::Pos{});
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    return v;
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}
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// Carefully walk an option path, looking for sub-options when a path walks past
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// an option value.
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struct FindAlongOptionPathRet
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{
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    Value option;
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    std::string path;
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};
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FindAlongOptionPathRet findAlongOptionPath(Context & ctx, const std::string & path)
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{
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    Strings tokens = parseAttrPath(path);
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    Value v = ctx.optionsRoot;
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    std::string processedPath;
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    for (auto i = tokens.begin(); i != tokens.end(); i++) {
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        const auto & attr = *i;
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        try {
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            bool lastAttribute = std::next(i) == tokens.end();
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            v = evaluateValue(ctx, v);
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            if (attr.empty()) {
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                throw OptionPathError("empty attribute name");
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            }
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            if (isOption(ctx, v) && optionTypeIs(ctx, v, "submodule")) {
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                v = getSubOptions(ctx, v);
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            }
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            if (isOption(ctx, v) && isAggregateOptionType(ctx, v)) {
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                auto subOptions = getSubOptions(ctx, v);
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                if (lastAttribute && subOptions.attrs->empty()) {
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                    break;
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                }
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                v = subOptions;
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                // Note that we've consumed attr, but didn't actually use it.  This is the path component that's looked
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                // up in the list or attribute set that doesn't name an option -- the "root" in "users.users.root.name".
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            } else if (v.type != tAttrs) {
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                throw OptionPathError("Value is %s while a set was expected", showType(v));
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            } else {
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                const auto & next = v.attrs->find(ctx.state.symbols.create(attr));
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                if (next == v.attrs->end()) {
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                    throw OptionPathError("Attribute not found", attr, path);
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                }
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                v = *next->value;
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            }
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            processedPath = appendPath(processedPath, attr);
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        } catch (OptionPathError & e) {
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            throw OptionPathError("At '%s' in path '%s': %s", attr, path, e.msg());
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        }
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    }
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    return {v, processedPath};
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}
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// Calls f on all the option names at or below the option described by `path`.
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// Note that "the option described by `path`" is not trivial -- if path describes a value inside an aggregate
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// option (such as users.users.root), the *option* described by that path is one path component shorter
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// (eg: users.users), which results in f being called on sibling-paths (eg: users.users.nixbld1).  If f
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// doesn't want these, it must do its own filtering.
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void mapOptions(const std::function<void(const std::string & path)> & f, Context & ctx, const std::string & path)
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{
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    auto root = findAlongOptionPath(ctx, path);
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    recurse(
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        [f, &ctx](const std::string & path, std::variant<Value, std::exception_ptr> v) {
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            bool isOpt = std::holds_alternative<std::exception_ptr>(v) || isOption(ctx, std::get<Value>(v));
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            if (isOpt) {
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                f(path);
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            }
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            return !isOpt;
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        },
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        ctx, root.option, root.path);
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}
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// Calls f on all the config values inside one option.
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// Simple options have one config value inside, like sound.enable = true.
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// Compound options have multiple config values.  For example, the option
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// "users.users" has about 1000 config values inside it:
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//   users.users.avahi.createHome = false;
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//   users.users.avahi.cryptHomeLuks = null;
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//   users.users.avahi.description = "`avahi-daemon' privilege separation user";
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//   ...
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//   users.users.avahi.openssh.authorizedKeys.keyFiles = [ ];
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//   users.users.avahi.openssh.authorizedKeys.keys = [ ];
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//   ...
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//   users.users.avahi.uid = 10;
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//   users.users.avahi.useDefaultShell = false;
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//   users.users.cups.createHome = false;
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//   ...
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//   users.users.cups.useDefaultShell = false;
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//   users.users.gdm = ... ... ...
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//   users.users.messagebus = ... .. ...
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//   users.users.nixbld1 = ... .. ...
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//   ...
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//   users.users.systemd-timesync = ... .. ...
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void mapConfigValuesInOption(
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    const std::function<void(const std::string & path, std::variant<Value, std::exception_ptr> v)> & f,
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    const std::string & path, Context & ctx)
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{
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    Value * option;
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    try {
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        option = findAlongAttrPath(ctx.state, path, ctx.autoArgs, ctx.configRoot);
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    } catch (Error &) {
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        f(path, std::current_exception());
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        return;
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    }
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    recurse(
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        [f, ctx](const std::string & path, std::variant<Value, std::exception_ptr> v) {
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            bool leaf = std::holds_alternative<std::exception_ptr>(v) || std::get<Value>(v).type != tAttrs ||
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                        ctx.state.isDerivation(std::get<Value>(v));
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            if (!leaf) {
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                return true; // Keep digging
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            }
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            f(path, v);
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            return false;
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        },
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        ctx, *option, path);
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}
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std::string describeError(const Error & e) { return "«error: " + e.msg() + "»"; }
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void describeDerivation(Context & ctx, Out & out, Value v)
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{
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    // Copy-pasted from nix/src/nix/repl.cc  :(
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    Bindings::iterator i = v.attrs->find(ctx.state.sDrvPath);
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    PathSet pathset;
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    try {
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        Path drvPath = i != v.attrs->end() ? ctx.state.coerceToPath(*i->pos, *i->value, pathset) : "???";
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        out << "«derivation " << drvPath << "»";
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    } catch (Error & e) {
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        out << describeError(e);
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    }
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}
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Value parseAndEval(EvalState & state, const std::string & expression, const std::string & path)
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{
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    Value v{};
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    state.eval(state.parseExprFromString(expression, absPath(path)), v);
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    return v;
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}
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void printValue(Context & ctx, Out & out, std::variant<Value, std::exception_ptr> maybeValue, const std::string & path);
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void printList(Context & ctx, Out & out, Value & v)
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{
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    Out listOut(out, "[", "]", v.listSize());
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    for (unsigned int n = 0; n < v.listSize(); ++n) {
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        printValue(ctx, listOut, *v.listElems()[n], "");
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        listOut << Out::sep;
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    }
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}
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void printAttrs(Context & ctx, Out & out, Value & v, const std::string & path)
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{
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    Out attrsOut(out, "{", "}", v.attrs->size());
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    for (const auto & a : v.attrs->lexicographicOrder()) {
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        std::string name = a->name;
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        if (!forbiddenRecursionName(name)) {
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            attrsOut << name << " = ";
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            printValue(ctx, attrsOut, *a->value, appendPath(path, name));
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            attrsOut << ";" << Out::sep;
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        }
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    }
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}
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void multiLineStringEscape(Out & out, const std::string & s)
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{
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    int i;
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    for (i = 1; i < s.size(); i++) {
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        if (s[i - 1] == '$' && s[i] == '{') {
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            out << "''${";
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            i++;
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        } else if (s[i - 1] == '\'' && s[i] == '\'') {
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            out << "'''";
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            i++;
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        } else {
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            out << s[i - 1];
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        }
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    }
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    if (i == s.size()) {
 | 
						|
        out << s[i - 1];
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void printMultiLineString(Out & out, const Value & v)
 | 
						|
{
 | 
						|
    std::string s = v.string.s;
 | 
						|
    Out strOut(out, "''", "''", Out::MULTI_LINE);
 | 
						|
    std::string::size_type begin = 0;
 | 
						|
    while (begin < s.size()) {
 | 
						|
        std::string::size_type end = s.find('\n', begin);
 | 
						|
        if (end == std::string::npos) {
 | 
						|
            multiLineStringEscape(strOut, s.substr(begin, s.size() - begin));
 | 
						|
            break;
 | 
						|
        }
 | 
						|
        multiLineStringEscape(strOut, s.substr(begin, end - begin));
 | 
						|
        strOut << Out::sep;
 | 
						|
        begin = end + 1;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void printValue(Context & ctx, Out & out, std::variant<Value, std::exception_ptr> maybeValue, const std::string & path)
 | 
						|
{
 | 
						|
    try {
 | 
						|
        if (auto ex = std::get_if<std::exception_ptr>(&maybeValue)) {
 | 
						|
            std::rethrow_exception(*ex);
 | 
						|
        }
 | 
						|
        Value v = evaluateValue(ctx, std::get<Value>(maybeValue));
 | 
						|
        if (ctx.state.isDerivation(v)) {
 | 
						|
            describeDerivation(ctx, out, v);
 | 
						|
        } else if (v.isList()) {
 | 
						|
            printList(ctx, out, v);
 | 
						|
        } else if (v.type == tAttrs) {
 | 
						|
            printAttrs(ctx, out, v, path);
 | 
						|
        } else if (v.type == tString && std::string(v.string.s).find('\n') != std::string::npos) {
 | 
						|
            printMultiLineString(out, v);
 | 
						|
        } else {
 | 
						|
            ctx.state.forceValueDeep(v);
 | 
						|
            out << v;
 | 
						|
        }
 | 
						|
    } catch (ThrownError & e) {
 | 
						|
        if (e.msg() == "The option `" + path + "' is used but not defined.") {
 | 
						|
            // 93% of errors are this, and just letting this message through would be
 | 
						|
            // misleading.  These values may or may not actually be "used" in the
 | 
						|
            // config.  The thing throwing the error message assumes that if anything
 | 
						|
            // ever looks at this value, it is a "use" of this value.  But here in
 | 
						|
            // nixos-option, we are looking at this value only to print it.
 | 
						|
            // In order to avoid implying that this undefined value is actually
 | 
						|
            // referenced, eat the underlying error message and emit "«not defined»".
 | 
						|
            out << "«not defined»";
 | 
						|
        } else {
 | 
						|
            out << describeError(e);
 | 
						|
        }
 | 
						|
    } catch (Error & e) {
 | 
						|
        out << describeError(e);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void printConfigValue(Context & ctx, Out & out, const std::string & path, std::variant<Value, std::exception_ptr> v)
 | 
						|
{
 | 
						|
    out << path << " = ";
 | 
						|
    printValue(ctx, out, std::move(v), path);
 | 
						|
    out << ";\n";
 | 
						|
}
 | 
						|
 | 
						|
// Replace with std::starts_with when C++20 is available
 | 
						|
bool starts_with(const std::string & s, const std::string & prefix)
 | 
						|
{
 | 
						|
    return s.size() >= prefix.size() &&
 | 
						|
           std::equal(s.begin(), std::next(s.begin(), prefix.size()), prefix.begin(), prefix.end());
 | 
						|
}
 | 
						|
 | 
						|
void printRecursive(Context & ctx, Out & out, const std::string & path)
 | 
						|
{
 | 
						|
    mapOptions(
 | 
						|
        [&ctx, &out, &path](const std::string & optionPath) {
 | 
						|
            mapConfigValuesInOption(
 | 
						|
                [&ctx, &out, &path](const std::string & configPath, std::variant<Value, std::exception_ptr> v) {
 | 
						|
                    if (starts_with(configPath, path)) {
 | 
						|
                        printConfigValue(ctx, out, configPath, v);
 | 
						|
                    }
 | 
						|
                },
 | 
						|
                optionPath, ctx);
 | 
						|
        },
 | 
						|
        ctx, path);
 | 
						|
}
 | 
						|
 | 
						|
void printAttr(Context & ctx, Out & out, const std::string & path, Value & root)
 | 
						|
{
 | 
						|
    try {
 | 
						|
        printValue(ctx, out, *findAlongAttrPath(ctx.state, path, ctx.autoArgs, root), path);
 | 
						|
    } catch (Error & e) {
 | 
						|
        out << describeError(e);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
bool hasExample(Context & ctx, Value & option)
 | 
						|
{
 | 
						|
    try {
 | 
						|
        findAlongAttrPath(ctx.state, "example", ctx.autoArgs, option);
 | 
						|
        return true;
 | 
						|
    } catch (Error &) {
 | 
						|
        return false;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void printOption(Context & ctx, Out & out, const std::string & path, Value & option)
 | 
						|
{
 | 
						|
    out << "Value:\n";
 | 
						|
    printAttr(ctx, out, path, ctx.configRoot);
 | 
						|
 | 
						|
    out << "\n\nDefault:\n";
 | 
						|
    printAttr(ctx, out, "default", option);
 | 
						|
 | 
						|
    out << "\n\nType:\n";
 | 
						|
    printAttr(ctx, out, "type.description", option);
 | 
						|
 | 
						|
    if (hasExample(ctx, option)) {
 | 
						|
        out << "\n\nExample:\n";
 | 
						|
        printAttr(ctx, out, "example", option);
 | 
						|
    }
 | 
						|
 | 
						|
    out << "\n\nDescription:\n";
 | 
						|
    printAttr(ctx, out, "description", option);
 | 
						|
 | 
						|
    out << "\n\nDeclared by:\n";
 | 
						|
    printAttr(ctx, out, "declarations", option);
 | 
						|
 | 
						|
    out << "\n\nDefined by:\n";
 | 
						|
    printAttr(ctx, out, "files", option);
 | 
						|
    out << "\n";
 | 
						|
}
 | 
						|
 | 
						|
void printListing(Out & out, Value & v)
 | 
						|
{
 | 
						|
    out << "This attribute set contains:\n";
 | 
						|
    for (const auto & a : v.attrs->lexicographicOrder()) {
 | 
						|
        std::string name = a->name;
 | 
						|
        if (!name.empty() && name[0] != '_') {
 | 
						|
            out << name << "\n";
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void printOne(Context & ctx, Out & out, const std::string & path)
 | 
						|
{
 | 
						|
    try {
 | 
						|
        auto result = findAlongOptionPath(ctx, path);
 | 
						|
        Value & option = result.option;
 | 
						|
        option = evaluateValue(ctx, option);
 | 
						|
        if (path != result.path) {
 | 
						|
            out << "Note: showing " << result.path << " instead of " << path << "\n";
 | 
						|
        }
 | 
						|
        if (isOption(ctx, option)) {
 | 
						|
            printOption(ctx, out, result.path, option);
 | 
						|
        } else {
 | 
						|
            printListing(out, option);
 | 
						|
        }
 | 
						|
    } catch (Error & e) {
 | 
						|
        std::cerr << "error: " << e.msg()
 | 
						|
                  << "\nAn error occurred while looking for attribute names. Are "
 | 
						|
                     "you sure that '"
 | 
						|
                  << path << "' exists?\n";
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
int main(int argc, char ** argv)
 | 
						|
{
 | 
						|
    bool recursive = false;
 | 
						|
    std::string path = ".";
 | 
						|
    std::string optionsExpr = "(import <nixpkgs/nixos> {}).options";
 | 
						|
    std::string configExpr = "(import <nixpkgs/nixos> {}).config";
 | 
						|
    std::vector<std::string> args;
 | 
						|
 | 
						|
    struct MyArgs : nix::LegacyArgs, nix::MixEvalArgs
 | 
						|
    {
 | 
						|
        using nix::LegacyArgs::LegacyArgs;
 | 
						|
    };
 | 
						|
 | 
						|
    MyArgs myArgs(nix::baseNameOf(argv[0]), [&](Strings::iterator & arg, const Strings::iterator & end) {
 | 
						|
        if (*arg == "--help") {
 | 
						|
            nix::showManPage("nixos-option");
 | 
						|
        } else if (*arg == "--version") {
 | 
						|
            nix::printVersion("nixos-option");
 | 
						|
        } else if (*arg == "-r" || *arg == "--recursive") {
 | 
						|
            recursive = true;
 | 
						|
        } else if (*arg == "--path") {
 | 
						|
            path = nix::getArg(*arg, arg, end);
 | 
						|
        } else if (*arg == "--options_expr") {
 | 
						|
            optionsExpr = nix::getArg(*arg, arg, end);
 | 
						|
        } else if (*arg == "--config_expr") {
 | 
						|
            configExpr = nix::getArg(*arg, arg, end);
 | 
						|
        } else if (!arg->empty() && arg->at(0) == '-') {
 | 
						|
            return false;
 | 
						|
        } else {
 | 
						|
            args.push_back(*arg);
 | 
						|
        }
 | 
						|
        return true;
 | 
						|
    });
 | 
						|
 | 
						|
    myArgs.parseCmdline(nix::argvToStrings(argc, argv));
 | 
						|
 | 
						|
    nix::initPlugins();
 | 
						|
    nix::initGC();
 | 
						|
    nix::settings.readOnlyMode = true;
 | 
						|
    auto store = nix::openStore();
 | 
						|
    auto state = std::make_unique<EvalState>(myArgs.searchPath, store);
 | 
						|
 | 
						|
    Value optionsRoot = parseAndEval(*state, optionsExpr, path);
 | 
						|
    Value configRoot = parseAndEval(*state, configExpr, path);
 | 
						|
 | 
						|
    Context ctx{*state, *myArgs.getAutoArgs(*state), optionsRoot, configRoot};
 | 
						|
    Out out(std::cout);
 | 
						|
 | 
						|
    auto print = recursive ? printRecursive : printOne;
 | 
						|
    if (args.empty()) {
 | 
						|
        print(ctx, out, "");
 | 
						|
    }
 | 
						|
    for (const auto & arg : args) {
 | 
						|
        print(ctx, out, arg);
 | 
						|
    }
 | 
						|
 | 
						|
    ctx.state.printStats();
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 |