3 files changed, 90 insertions, 68 deletions
diff --git a/src/libmain/common-args.cc b/src/libmain/common-args.cc
index 3fa42c2aafa9..ea27aaa35e03 100644
--- a/src/libmain/common-args.cc
+++ b/src/libmain/common-args.cc
@@ -6,28 +6,30 @@ namespace nix {
 MixCommonArgs::MixCommonArgs(const string & programName)
     : programName(programName)
 {
-    mkFlag('v', "verbose", "increase verbosity level", []() {
-        verbosity = (Verbosity) (verbosity + 1);
-    });
+    mkFlag()
+        .longName("verbose")
+        .shortName('v')
+        .description("increase verbosity level")
+        .handler([]() { verbosity = (Verbosity) (verbosity + 1); });
 
-    mkFlag(0, "quiet", "decrease verbosity level", []() {
-        verbosity = verbosity > lvlError ? (Verbosity) (verbosity - 1) : lvlError;
-    });
+    mkFlag()
+        .longName("quiet")
+        .description("decrease verbosity level")
+        .handler([]() { verbosity = verbosity > lvlError ? (Verbosity) (verbosity - 1) : lvlError; });
 
-    mkFlag(0, "debug", "enable debug output", []() {
-        verbosity = lvlDebug;
-    });
+    mkFlag()
+        .longName("debug")
+        .description("enable debug output")
+        .handler([]() { verbosity = lvlDebug; });
 
     mkFlag()
         .longName("option")
         .labels({"name", "value"})
         .description("set a Nix configuration option (overriding nix.conf)")
         .arity(2)
-        .handler([](Strings ss) {
-            auto name = ss.front(); ss.pop_front();
-            auto value = ss.front();
+        .handler([](std::vector<std::string> ss) {
             try {
-                settings.set(name, value);
+                settings.set(ss[0], ss[1]);
             } catch (UsageError & e) {
                 warn(e.what());
             }
diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc
index aef5d88bf46f..9123a3d1ae04 100644
--- a/src/libmain/shared.cc
+++ b/src/libmain/shared.cc
@@ -1,4 +1,3 @@
-#include "common-args.hh"
 #include "globals.hh"
 #include "shared.hh"
 #include "store-api.hh"
@@ -149,71 +148,78 @@ void initNix()
 }
 
 
-struct LegacyArgs : public MixCommonArgs
+LegacyArgs::LegacyArgs(const std::string & programName,
+    std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg)
+    : MixCommonArgs(programName), parseArg(parseArg)
 {
-    std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg;
-
-    LegacyArgs(const std::string & programName,
-        std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg)
-        : MixCommonArgs(programName), parseArg(parseArg)
-    {
-        mkFlag('Q', "no-build-output", "do not show build output",
-            &settings.verboseBuild, false);
-
-        mkFlag('K', "keep-failed", "keep temporary directories of failed builds",
-            &(bool&) settings.keepFailed);
-
-        mkFlag('k', "keep-going", "keep going after a build fails",
-            &(bool&) settings.keepGoing);
+    mkFlag()
+        .longName("no-build-output")
+        .shortName('Q')
+        .description("do not show build output")
+        .set(&settings.verboseBuild, false);
+
+    mkFlag()
+        .longName("keep-failed")
+        .shortName('K')
+        .description("keep temporary directories of failed builds")
+        .set(&(bool&) settings.keepFailed, true);
+
+    mkFlag()
+        .longName("keep-going")
+        .shortName('k')
+        .description("keep going after a build fails")
+        .set(&(bool&) settings.keepGoing, true);
+
+    mkFlag()
+        .longName("fallback")
+        .description("build from source if substitution fails")
+        .set(&(bool&) settings.tryFallback, true);
+
+    mkFlag1('j', "max-jobs", "jobs", "maximum number of parallel builds", [=](std::string s) {
+        settings.set("max-jobs", s);
+    });
 
-        mkFlag(0, "fallback", "build from source if substitution fails", []() {
-            settings.tryFallback = true;
+    auto intSettingAlias = [&](char shortName, const std::string & longName,
+        const std::string & description, const std::string & dest) {
+        mkFlag<unsigned int>(shortName, longName, description, [=](unsigned int n) {
+            settings.set(dest, std::to_string(n));
         });
+    };
 
-        mkFlag1('j', "max-jobs", "jobs", "maximum number of parallel builds", [=](std::string s) {
-            settings.set("max-jobs", s);
-        });
+    intSettingAlias(0, "cores", "maximum number of CPU cores to use inside a build", "cores");
+    intSettingAlias(0, "max-silent-time", "number of seconds of silence before a build is killed", "max-silent-time");
+    intSettingAlias(0, "timeout", "number of seconds before a build is killed", "timeout");
 
-        auto intSettingAlias = [&](char shortName, const std::string & longName,
-            const std::string & description, const std::string & dest) {
-            mkFlag<unsigned int>(shortName, longName, description, [=](unsigned int n) {
-                settings.set(dest, std::to_string(n));
-            });
-        };
+    mkFlag(0, "readonly-mode", "do not write to the Nix store",
+        &settings.readOnlyMode);
 
-        intSettingAlias(0, "cores", "maximum number of CPU cores to use inside a build", "cores");
-        intSettingAlias(0, "max-silent-time", "number of seconds of silence before a build is killed", "max-silent-time");
-        intSettingAlias(0, "timeout", "number of seconds before a build is killed", "timeout");
+    mkFlag(0, "show-trace", "show Nix expression stack trace in evaluation errors",
+        &settings.showTrace);
 
-        mkFlag(0, "readonly-mode", "do not write to the Nix store",
-            &settings.readOnlyMode);
+    mkFlag(0, "no-gc-warning", "disable warning about not using '--add-root'",
+        &gcWarning, false);
+}
 
-        mkFlag(0, "show-trace", "show Nix expression stack trace in evaluation errors",
-            &settings.showTrace);
 
-        mkFlag(0, "no-gc-warning", "disable warning about not using '--add-root'",
-            &gcWarning, false);
-    }
+bool LegacyArgs::processFlag(Strings::iterator & pos, Strings::iterator end)
+{
+    if (MixCommonArgs::processFlag(pos, end)) return true;
+    bool res = parseArg(pos, end);
+    if (res) ++pos;
+    return res;
+}
 
-    bool processFlag(Strings::iterator & pos, Strings::iterator end) override
-    {
-        if (MixCommonArgs::processFlag(pos, end)) return true;
-        bool res = parseArg(pos, end);
-        if (res) ++pos;
-        return res;
-    }
 
-    bool processArgs(const Strings & args, bool finish) override
-    {
-        if (args.empty()) return true;
-        assert(args.size() == 1);
-        Strings ss(args);
-        auto pos = ss.begin();
-        if (!parseArg(pos, ss.end()))
-            throw UsageError(format("unexpected argument '%1%'") % args.front());
-        return true;
-    }
-};
+bool LegacyArgs::processArgs(const Strings & args, bool finish)
+{
+    if (args.empty()) return true;
+    assert(args.size() == 1);
+    Strings ss(args);
+    auto pos = ss.begin();
+    if (!parseArg(pos, ss.end()))
+        throw UsageError(format("unexpected argument '%1%'") % args.front());
+    return true;
+}
 
 
 void parseCmdLine(int argc, char * * argv,
diff --git a/src/libmain/shared.hh b/src/libmain/shared.hh
index 2a1e42dd9774..9219dbed8325 100644
--- a/src/libmain/shared.hh
+++ b/src/libmain/shared.hh
@@ -2,6 +2,7 @@
 
 #include "util.hh"
 #include "args.hh"
+#include "common-args.hh"
 
 #include <signal.h>
 
@@ -69,6 +70,19 @@ template<class N> N getIntArg(const string & opt,
 }
 
 
+struct LegacyArgs : public MixCommonArgs
+{
+    std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg;
+
+    LegacyArgs(const std::string & programName,
+        std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg);
+
+    bool processFlag(Strings::iterator & pos, Strings::iterator end) override;
+
+    bool processArgs(const Strings & args, bool finish) override;
+};
+
+
 /* Show the manual page for the specified program. */
 void showManPage(const string & name);