* Implemented `rec { inherit ...; }'.

This commit is contained in:
Eelco Dolstra 2010-03-31 11:05:39 +00:00
parent 4c53ca2692
commit 13c2adc897
2 changed files with 17 additions and 0 deletions

View file

@ -73,6 +73,9 @@ void run(Strings args)
doTest("map (x: __add 1 x) [ 1 2 3 ]"); doTest("map (x: __add 1 x) [ 1 2 3 ]");
doTest("map (builtins.add 1) [ 1 2 3 ]"); doTest("map (builtins.add 1) [ 1 2 3 ]");
doTest("builtins.hasAttr \"x\" { x = 1; }"); doTest("builtins.hasAttr \"x\" { x = 1; }");
doTest("let x = 1; as = rec { inherit x; y = as.x; }; in as.y");
doTest("let as = { x = 1; }; bs = rec { inherit (as) x; y = x; }; in bs.y");
doTest("let as = rec { inherit (y) x; y = { x = 1; }; }; in as.x");
} }

View file

@ -326,11 +326,16 @@ void EvalState::eval(Env & env, Expr e, Value & v)
} }
else if (matchRec(e, rbnds, nrbnds)) { else if (matchRec(e, rbnds, nrbnds)) {
/* Create a new environment that contains the attributes in
this `rec'. */
Env & env2(allocEnv()); Env & env2(allocEnv());
env2.up = &env; env2.up = &env;
v.type = tAttrs; v.type = tAttrs;
v.attrs = &env2.bindings; v.attrs = &env2.bindings;
/* The recursive attributes are evaluated in the new
environment. */
ATerm name, e2, pos; ATerm name, e2, pos;
for (ATermIterator i(rbnds); i; ++i) { for (ATermIterator i(rbnds); i; ++i) {
if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
@ -338,6 +343,15 @@ void EvalState::eval(Env & env, Expr e, Value & v)
nrValues++; nrValues++;
mkThunk(v2, env2, e2); mkThunk(v2, env2, e2);
} }
/* The non-recursive attributes, on the other hand, are
evaluated in the original environment. */
for (ATermIterator i(nrbnds); i; ++i) {
if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
Value & v2 = env2.bindings[name];
nrValues++;
mkThunk(v2, env, e2);
}
} }
else if (matchSelect(e, e2, name)) { else if (matchSelect(e, e2, name)) {