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-rw-r--r--src/libexpr/eval-test.cc2
-rw-r--r--src/libexpr/eval.cc210
-rw-r--r--src/libexpr/eval.hh13
-rw-r--r--src/libexpr/primops.cc22
4 files changed, 139 insertions, 108 deletions
diff --git a/src/libexpr/eval-test.cc b/src/libexpr/eval-test.cc
index 8aade1298..0b20883a3 100644
--- a/src/libexpr/eval-test.cc
+++ b/src/libexpr/eval-test.cc
@@ -68,6 +68,8 @@ void run(Strings args)
doTest("let x = x; in if true || x then 1 else 2");
doTest("/etc/passwd");
doTest("import ./foo.nix");
+ doTest("map (x: __add 1 x) [ 1 2 3 ]");
+ doTest("map (__add 1) [ 1 2 3 ]");
}
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 86484031b..f1437e465 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -328,106 +328,9 @@ void EvalState::eval(Env & env, Expr e, Value & v)
Expr fun, arg;
if (matchCall(e, fun, arg)) {
eval(env, fun, v);
-
- if (v.type == tPrimOp || v.type == tPrimOpApp) {
- unsigned int argsLeft =
- v.type == tPrimOp ? v.primOp.arity : v.primOpApp.argsLeft;
- if (argsLeft == 1) {
- /* We have all the arguments, so call the primop.
- First find the primop. */
- Value * primOp = &v;
- while (primOp->type == tPrimOpApp) primOp = primOp->primOpApp.left;
- assert(primOp->type == tPrimOp);
- unsigned int arity = primOp->primOp.arity;
-
- Value vLastArg;
- mkThunk(vLastArg, env, arg);
-
- /* Put all the arguments in an array. */
- Value * vArgs[arity];
- unsigned int n = arity - 1;
- vArgs[n--] = &vLastArg;
- for (Value * arg = &v; arg->type == tPrimOpApp; arg = arg->primOpApp.left)
- vArgs[n--] = arg->primOpApp.right;
-
- /* And call the primop. */
- primOp->primOp.fun(*this, vArgs, v);
- } else {
- Value * v2 = allocValues(2);
- v2[0] = v;
- mkThunk(v2[1], env, arg);
- v.type = tPrimOpApp;
- v.primOpApp.left = &v2[0];
- v.primOpApp.right = &v2[1];
- v.primOpApp.argsLeft = argsLeft - 1;
- }
- return;
- }
-
- if (v.type != tLambda) throw TypeError("expected function");
-
- Env & env2(allocEnv());
- env2.up = &env;
-
- ATermList formals; ATerm ellipsis;
-
- if (matchVarPat(v.lambda.pat, name)) {
- Value & vArg = env2.bindings[name];
- nrValues++;
- mkThunk(vArg, env, arg);
- }
-
- else if (matchAttrsPat(v.lambda.pat, formals, ellipsis, name)) {
- Value * vArg;
- Value vArg_;
-
- if (name == sNoAlias)
- vArg = &vArg_;
- else {
- vArg = &env2.bindings[name];
- nrValues++;
- }
-
- eval(env, arg, *vArg);
- forceAttrs(*vArg);
-
- /* For each formal argument, get the actual argument. If
- there is no matching actual argument but the formal
- argument has a default, use the default. */
- unsigned int attrsUsed = 0;
- for (ATermIterator i(formals); i; ++i) {
- Expr def; Sym name;
- DefaultValue def2;
- if (!matchFormal(*i, name, def2)) abort(); /* can't happen */
-
- Bindings::iterator j = vArg->attrs->find(name);
-
- Value & v = env2.bindings[name];
- nrValues++;
-
- if (j == vArg->attrs->end()) {
- if (!matchDefaultValue(def2, def)) def = 0;
- if (def == 0) throw TypeError(format("the argument named `%1%' required by the function is missing")
- % aterm2String(name));
- mkThunk(v, env2, def);
- } else {
- attrsUsed++;
- v.type = tCopy;
- v.val = &j->second;
- }
- }
-
- /* Check that each actual argument is listed as a formal
- argument (unless the attribute match specifies a
- `...'). TODO: show the names of the
- expected/unexpected arguments. */
- if (ellipsis == eFalse && attrsUsed != vArg->attrs->size())
- throw TypeError("function called with unexpected argument");
- }
-
- else abort();
-
- eval(env2, v.lambda.body, v);
+ Value vArg;
+ mkThunk(vArg, env, arg); // !!! should this be on the heap?
+ callFunction(v, vArg, v);
return;
}
@@ -519,6 +422,103 @@ void EvalState::eval(Env & env, Expr e, Value & v)
}
+void EvalState::callFunction(Value & fun, Value & arg, Value & v)
+{
+ if (fun.type == tPrimOp || fun.type == tPrimOpApp) {
+ unsigned int argsLeft =
+ fun.type == tPrimOp ? fun.primOp.arity : fun.primOpApp.argsLeft;
+ if (argsLeft == 1) {
+ /* We have all the arguments, so call the primop. First
+ find the primop. */
+ Value * primOp = &fun;
+ while (primOp->type == tPrimOpApp) primOp = primOp->primOpApp.left;
+ assert(primOp->type == tPrimOp);
+ unsigned int arity = primOp->primOp.arity;
+
+ /* Put all the arguments in an array. */
+ Value * vArgs[arity];
+ unsigned int n = arity - 1;
+ vArgs[n--] = &arg;
+ for (Value * arg = &fun; arg->type == tPrimOpApp; arg = arg->primOpApp.left)
+ vArgs[n--] = arg->primOpApp.right;
+
+ /* And call the primop. */
+ primOp->primOp.fun(*this, vArgs, v);
+ } else {
+ Value * v2 = allocValues(2);
+ v2[0] = fun;
+ v2[1] = arg;
+ v.type = tPrimOpApp;
+ v.primOpApp.left = &v2[0];
+ v.primOpApp.right = &v2[1];
+ v.primOpApp.argsLeft = argsLeft - 1;
+ }
+ return;
+ }
+
+ if (fun.type != tLambda)
+ throwTypeError("attempt to call something which is neither a function nor a primop (built-in operation) but %1%",
+ showType(fun));
+
+ Env & env2(allocEnv());
+ env2.up = fun.lambda.env;
+
+ ATermList formals; ATerm ellipsis, name;
+
+ if (matchVarPat(fun.lambda.pat, name)) {
+ Value & vArg = env2.bindings[name];
+ nrValues++;
+ vArg = arg;
+ }
+
+ else if (matchAttrsPat(fun.lambda.pat, formals, ellipsis, name)) {
+ forceAttrs(arg);
+
+ if (name != sNoAlias) {
+ env2.bindings[name] = arg;
+ nrValues++;
+ }
+
+ /* For each formal argument, get the actual argument. If
+ there is no matching actual argument but the formal
+ argument has a default, use the default. */
+ unsigned int attrsUsed = 0;
+ for (ATermIterator i(formals); i; ++i) {
+ Expr def; Sym name;
+ DefaultValue def2;
+ if (!matchFormal(*i, name, def2)) abort(); /* can't happen */
+
+ Bindings::iterator j = arg.attrs->find(name);
+
+ Value & v = env2.bindings[name];
+ nrValues++;
+
+ if (j == arg.attrs->end()) {
+ if (!matchDefaultValue(def2, def)) def = 0;
+ if (def == 0) throw TypeError(format("the argument named `%1%' required by the function is missing")
+ % aterm2String(name));
+ mkThunk(v, env2, def);
+ } else {
+ attrsUsed++;
+ v.type = tCopy;
+ v.val = &j->second;
+ }
+ }
+
+ /* Check that each actual argument is listed as a formal
+ argument (unless the attribute match specifies a `...').
+ TODO: show the names of the expected/unexpected
+ arguments. */
+ if (ellipsis == eFalse && attrsUsed != arg.attrs->size())
+ throw TypeError("function called with unexpected argument");
+ }
+
+ else abort();
+
+ eval(env2, fun.lambda.body, v);
+}
+
+
void EvalState::eval(Expr e, Value & v)
{
eval(baseEnv, e, v);
@@ -567,6 +567,8 @@ void EvalState::forceValue(Value & v)
forceValue(*v.val);
v = *v.val;
}
+ else if (v.type == tApp)
+ callFunction(*v.app.left, *v.app.right, v);
else if (v.type == tBlackhole)
throw EvalError("infinite recursion encountered");
}
@@ -597,6 +599,14 @@ void EvalState::forceList(Value & v)
}
+void EvalState::forceFunction(Value & v)
+{
+ forceValue(v);
+ if (v.type != tLambda && v.type != tPrimOp && v.type != tPrimOpApp)
+ throw TypeError(format("value is %1% while a function was expected") % showType(v));
+}
+
+
string EvalState::coerceToString(Value & v, PathSet & context,
bool coerceMore, bool copyToStore)
{
diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index 4706602d5..385c2d78d 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -36,6 +36,7 @@ typedef enum {
tAttrs,
tList,
tThunk,
+ tApp,
tLambda,
tCopy,
tBlackhole,
@@ -69,6 +70,9 @@ struct Value
Expr expr;
} thunk;
struct {
+ Value * left, * right;
+ } app;
+ struct {
Env * env;
Pattern pat;
Expr body;
@@ -161,13 +165,16 @@ struct EvalState
void strictEval(Env & env, Expr e, Value & v);
/* If `v' is a thunk, enter it and overwrite `v' with the result
- of the evaluation of the thunk. Otherwise, this is a no-op. */
+ of the evaluation of the thunk. If `v' is a delayed function
+ application, call the function and overwrite `v' with the
+ result. Otherwise, this is a no-op. */
void forceValue(Value & v);
/* Force `v', and then verify that it has the expected type. */
int forceInt(Value & v);
void forceAttrs(Value & v);
void forceList(Value & v);
+ void forceFunction(Value & v); // either lambda or primop
/* String coercion. Converts strings, paths and derivations to a
string. If `coerceMore' is set, also converts nulls, integers,
@@ -196,6 +203,10 @@ private:
elements and attributes are compared recursively. */
bool eqValues(Value & v1, Value & v2);
+ void callFunction(Value & fun, Value & arg, Value & v);
+
+public:
+
/* Allocation primitives. */
Value * allocValues(unsigned int count);
Env & allocEnv();
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 2815567e5..bf8271b13 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -913,22 +913,28 @@ static Expr prim_tail(EvalState & state, const ATermVector & args)
throw Error("`tail' called on an empty list");
return makeList(ATgetNext(list));
}
+#endif
/* Apply a function to every element of a list. */
-static Expr prim_map(EvalState & state, const ATermVector & args)
+static void prim_map(EvalState & state, Value * * args, Value & v)
{
- Expr fun = evalExpr(state, args[0]);
- ATermList list = evalList(state, args[1]);
+ state.forceFunction(*args[0]);
+ state.forceList(*args[1]);
- ATermList res = ATempty;
- for (ATermIterator i(list); i; ++i)
- res = ATinsert(res, makeCall(fun, *i));
+ v.type = tList;
+ v.list.length = args[1]->list.length;
+ v.list.elems = state.allocValues(v.list.length);
- return makeList(ATreverse(res));
+ for (unsigned int n = 0; n < v.list.length; ++n) {
+ v.list.elems[n].type = tApp;
+ v.list.elems[n].app.left = args[0];
+ v.list.elems[n].app.right = &args[1]->list.elems[n];
+ }
}
+#if 0
/* Return the length of a list. This is an O(1) time operation. */
static Expr prim_length(EvalState & state, const ATermVector & args)
{
@@ -1189,7 +1195,9 @@ void EvalState::createBaseEnv()
addPrimOp("__head", 1, prim_head);
#if 0
addPrimOp("__tail", 1, prim_tail);
+#endif
addPrimOp("map", 2, prim_map);
+#if 0
addPrimOp("__length", 1, prim_length);
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 15:12:38 +0000