diff options
| -rw-r--r-- | src/libexpr/primops.cc | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 01f933da1..bdf8dddca 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -23,6 +23,18 @@ namespace nix { *************************************************************/ +/* Decode a context string ‘!<name>!<path>’ into a pair <path, + name>. */ +std::pair<string, string> decodeContext(const string & s) +{ + if (s.at(0) == '!') { + size_t index = s.find("!", 1); + return std::pair<string, string>(string(s, index + 1), string(s, 1, index - 1)); + } else + return std::pair<string, string>(s, ""); +} + + /* Load and evaluate an expression from path specified by the argument. */ static void prim_import(EvalState & state, Value * * args, Value & v) @@ -30,14 +42,17 @@ static void prim_import(EvalState & state, Value * * args, Value & v) PathSet context; Path path = state.coerceToPath(*args[0], context); - for (PathSet::iterator i = context.begin(); i != context.end(); ++i) { - assert(isStorePath(*i)); - if (!store->isValidPath(*i)) + foreach (PathSet::iterator, i, context) { + Path ctx = decodeContext(*i).first; + assert(isStorePath(ctx)); + if (!store->isValidPath(ctx)) throw EvalError(format("cannot import `%1%', since path `%2%' is not valid") - % path % *i); - if (isDerivation(*i)) + % path % ctx); + if (isDerivation(ctx)) try { - store->buildDerivations(singleton<PathSet>(*i)); + /* !!! If using a substitute, we only need to fetch + the selected output of this derivation. */ + store->buildDerivations(singleton<PathSet>(ctx)); } catch (Error & e) { throw ImportError(e.msg()); } @@ -374,8 +389,8 @@ static void prim_derivationStrict(EvalState & state, Value * * args, Value & v) /* Handle derivation outputs of the form ‘!<name>!<path>’. */ else if (path.at(0) == '!') { - size_t index = path.find("!", 1); - drv.inputDrvs[string(path, index + 1)].insert(string(path, 1, index - 1)); + std::pair<string, string> ctx = decodeContext(path); + drv.inputDrvs[ctx.first].insert(ctx.second); } /* Handle derivation contexts returned by |