nixos/nix
1
1
Fork 0
mirror of https://github.com/NixOS/nix.git synced 2025-11-15 06:52:43 +01:00
Code Activity

* The `import' primop now accepts derivations. These are first

Browse source 
realised, and then the file at the derivation's output path is
  loaded as a Nix expression.
This commit is contained in:
Eelco Dolstra 2004-07-06 15:57:39 +00:00
parent 321be4649d
commit fa50c0849e
1 changed files with 30 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

34
src/libexpr/primops.cc
View file

@ -6,9 +6,35 @@
Expr primImport(EvalState & state, Expr arg) Expr primImport(EvalState & state, Expr arg)
{ {
ATMatcher m; ATMatcher m;
string path; ATermList es;
if (!(atMatch(m, arg) >> "Path" >> path)) Path path;
throw Error("path expected");
arg = evalExpr(state, arg);
if (atMatch(m, arg) >> "Path" >> path)
;
else if (atMatch(m, arg) >> "Attrs" >> es) {
Expr a = queryAttr(arg, "type");
/* If it is a derivation, we have to realise it and load the
Nix expression created at the derivation's output path. */
if (a && evalString(state, a) == "derivation") {
a = queryAttr(arg, "drvPath");
if (!a) throw Error("bad derivation in import");
Path drvPath = evalPath(state, a);
realiseStoreExpr(drvPath);
a = queryAttr(arg, "outPath");
if (!a) throw Error("bad derivation in import");
path = evalPath(state, a);
}
}
if (path == "")
throw Error("path or derivation expected in import");
return evalFile(state, path); return evalFile(state, path);
} }
@ -267,7 +293,7 @@ Expr primToString(EvalState & state, Expr arg)
atMatch(m, arg) >> "Path" >> s || atMatch(m, arg) >> "Path" >> s ||
atMatch(m, arg) >> "Uri" >> s) atMatch(m, arg) >> "Uri" >> s)
return ATmake("Str(<str>)", s.c_str()); return ATmake("Str(<str>)", s.c_str());
else throw Error("cannot coerce value to string"); throw Error("cannot coerce value to string");
} }