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diff --git a/sca-cpp/branches/lightweight-sca/modules/server/mod-scheme.hpp b/sca-cpp/branches/lightweight-sca/modules/server/mod-scheme.hpp
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/* $Rev$ $Date$ */
+
+#ifndef tuscany_modscheme_hpp
+#define tuscany_modscheme_hpp
+
+/**
+ * Evaluation functions used by mod-eval to evaluate Scheme
+ * component implementations.
+ */
+
+#include "string.hpp"
+#include "stream.hpp"
+#include "function.hpp"
+#include "list.hpp"
+#include "value.hpp"
+#include "monad.hpp"
+#include "../scheme/eval.hpp"
+
+namespace tuscany {
+namespace server {
+namespace modscheme {
+
+/**
+ * Convert proxy lambdas to evaluator primitive procedures.
+ */
+const list<value> primitiveProcedures(const list<value>& l) {
+    if (isNil(l))
+        return l;
+    return cons<value>(mklist<value>(scheme::primitiveSymbol, car(l)), primitiveProcedures(cdr(l)));
+}
+
+/**
+ * Apply a Scheme component implementation function.
+ */
+struct applyImplementation {
+    const value impl;
+    const list<value> px;
+
+    applyImplementation(const value& impl, const list<value>& px) : impl(impl), px(scheme::quotedParameters(primitiveProcedures(px))) {
+    }
+
+    const value operator()(const list<value>& params) const {
+        const value expr = cons<value>(car(params), append(scheme::quotedParameters(cdr(params)), px));
+        debug(expr, "modeval::scheme::applyImplementation::input");
+        scheme::Env env = scheme::setupEnvironment();
+        const value res = scheme::evalScript(expr, impl, env);
+        const value val = isNil(res)? mklist<value>(value(), string("Could not evaluate expression")) : mklist<value>(res);
+        debug(val, "modeval::scheme::applyImplementation::result");
+        return val;
+    }
+};
+
+/**
+ * Evaluate a Scheme component implementation and convert it to an
+ * applicable lambda function.
+ */
+const failable<lambda<value(const list<value>&)> > evalImplementation(const string& path, const value& impl, const list<value>& px) {
+    const string fpath(path + attributeValue("script", impl));
+    ifstream is(fpath);
+    if (fail(is))
+        return mkfailure<lambda<value(const list<value>&)> >(string("Could not read implementation: ") + fpath);
+    const value script = scheme::readScript(is);
+    if (isNil(script))
+        return mkfailure<lambda<value(const list<value>&)> >(string("Could not read implementation: ") + fpath);
+    return lambda<value(const list<value>&)>(applyImplementation(script, px));
+}
+
+}
+}
+}
+
+#endif /* tuscany_modscheme_hpp */