diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/libexpr/eval-test.cc | 64 |
1 files changed, 38 insertions, 26 deletions
diff --git a/src/libexpr/eval-test.cc b/src/libexpr/eval-test.cc index c4fb7d1846ca..ee95fc1e780c 100644 --- a/src/libexpr/eval-test.cc +++ b/src/libexpr/eval-test.cc @@ -73,14 +73,13 @@ std::ostream & operator << (std::ostream & str, Value_ & v) } -Value eval(Env env, Expr e); +void eval(Env env, Expr e, Value v); void forceValue(Value v) { if (v->type != tThunk) return; - Value v2 = eval(v->thunk.env, v->thunk.expr); - *v = *v2; // !!! slightly inefficient + eval(v->thunk.env, v->thunk.expr, v); } @@ -94,40 +93,48 @@ Value lookupVar(Env env, const string & name) } -Value eval(Env env, Expr e) +unsigned long nrValues = 0; + +Value allocValue() +{ + nrValues++; + return new Value_; +} + + +void eval(Env env, Expr e, Value v) { printMsg(lvlError, format("eval: %1%") % e); ATerm name; if (matchVar(e, name)) { - Value v = lookupVar(env, aterm2String(name)); - forceValue(v); - return v; + Value v2 = lookupVar(env, aterm2String(name)); + forceValue(v2); + *v = *v2; + return; } int n; if (matchInt(e, n)) { - Value v = new Value_; v->type = tInt; v->integer = n; - return v; + return; } ATermList es; if (matchAttrs(e, es)) { - Value v = new Value_; v->type = tAttrs; v->attrs = new Bindings; ATerm e2, pos; for (ATermIterator i(es); i; ++i) { if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - Value v2 = new Value_; + Value v2 = allocValue(); v2->type = tThunk; v2->thunk.env = env; v2->thunk.expr = e2; (*v->attrs)[aterm2String(name)] = v2; } - return v; + return; } ATermList rbnds, nrbnds; @@ -135,48 +142,48 @@ Value eval(Env env, Expr e) Env env2 = new Env_; env2->up = env; - Value v = new Value_; v->type = tAttrs; v->attrs = &env2->bindings; ATerm name, e2, pos; for (ATermIterator i(rbnds); i; ++i) { if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - Value v2 = new Value_; + Value v2 = allocValue(); v2->type = tThunk; v2->thunk.env = env2; v2->thunk.expr = e2; env2->bindings[aterm2String(name)] = v2; } - return v; + + return; } Expr e2; if (matchSelect(e, e2, name)) { - Value v = eval(env, e2); + eval(env, e2, v); if (v->type != tAttrs) throw TypeError("expected attribute set"); Value v2 = (*v->attrs)[aterm2String(name)]; if (!v2) throw TypeError("attribute not found"); forceValue(v2); - return v2; + *v = *v2; + return; } Pattern pat; Expr body; Pos pos; if (matchFunction(e, pat, body, pos)) { - Value v = new Value_; v->type = tLambda; v->lambda.env = env; v->lambda.pat = pat; v->lambda.body = body; - return v; + return; } Expr fun, arg; if (matchCall(e, fun, arg)) { - Value fun_ = eval(env, fun); - if (fun_->type != tLambda) throw TypeError("expected function"); - if (!matchVarPat(fun_->lambda.pat, name)) throw Error("not implemented"); + eval(env, fun, v); + if (v->type != tLambda) throw TypeError("expected function"); + if (!matchVarPat(v->lambda.pat, name)) throw Error("not implemented"); - Value arg_ = new Value_; + Value arg_ = allocValue(); arg_->type = tThunk; arg_->thunk.env = env; arg_->thunk.expr = arg; @@ -185,7 +192,8 @@ Value eval(Env env, Expr e) env2->up = env; env2->bindings[aterm2String(name)] = arg_; - return eval(env2, fun_->lambda.body); + eval(env2, v->lambda.body, v); + return; } abort(); @@ -197,8 +205,9 @@ void doTest(string s) EvalState state; Expr e = parseExprFromString(state, s, "/"); printMsg(lvlError, format("%1%") % e); - Value v = eval(0, e); - printMsg(lvlError, format("result: %1%") % *v); + Value_ v; + eval(0, e, &v); + printMsg(lvlError, format("result: %1%") % v); } @@ -212,10 +221,13 @@ void run(Strings args) doTest("rec { x = 1; y = x; }.y"); doTest("(x: x) 1"); doTest("(x: y: y) 1 2"); + //Expr e = parseExprFromString(state, "let x = \"a\"; in x + \"b\"", "/"); //Expr e = parseExprFromString(state, "(x: x + \"b\") \"a\"", "/"); //Expr e = parseExprFromString(state, "\"a\" + \"b\"", "/"); //Expr e = parseExprFromString(state, "\"a\" + \"b\"", "/"); + + printMsg(lvlError, format("alloced %1% values") % nrValues); } |