Minor refactoring, given each module its own namespace. Added utility functions to convert between values elements/attributes and fixed XML, ATOM and JSON serialization of lists.

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@829699 13f79535-47bb-0310-9956-ffa450edef68

8 files changed, 70 insertions, 44 deletions

diff --git a/cpp/sca/modules/eval/Makefile.am b/cpp/sca/modules/eval/Makefile.am
index 552e0f99c7..b9fa9f8f56 100644
--- a/cpp/sca/modules/eval/Makefile.am
+++ b/cpp/sca/modules/eval/Makefile.am
@@ -27,3 +27,6 @@ eval_test_LDADD = -lpthread -L${LIBXML2_LIB} -lxml2
 
 eval_shell_SOURCES = eval-shell.cpp
 eval_shell_LDADD = -lpthread -L${LIBXML2_LIB} -lxml2
+
+TESTS = eval-test
+
diff --git a/cpp/sca/modules/eval/driver.hpp b/cpp/sca/modules/eval/driver.hpp
index 7a0645781f..064213706c 100644
--- a/cpp/sca/modules/eval/driver.hpp
+++ b/cpp/sca/modules/eval/driver.hpp
@@ -31,6 +31,7 @@
 #include "eval.hpp"
 
 namespace tuscany {
+namespace eval {
 
 const std::string evalOutputPrompt("; ");
 const std::string evalInputPrompt("=> ");
@@ -57,7 +58,7 @@ const value evalDriverLoop(std::istream& in, std::ostream& out, Env& globalEnv)
     value input = read(in);
     if (isNil(input))
         return input;
-    const value output = eval(input, globalEnv);
+    const value output = evalApply(input, globalEnv);
     announceOutput(out, evalOutputPrompt);
     userPrint(out, output);
     return evalDriverLoop(in, out, globalEnv);
@@ -71,4 +72,5 @@ const bool evalDriverRun(std::istream& in, std::ostream& out) {
 }
 
 }
+}
 #endif /* tuscany_eval_driver_hpp */
diff --git a/cpp/sca/modules/eval/environment.hpp b/cpp/sca/modules/eval/environment.hpp
index 834563069e..e0da9096fe 100644
--- a/cpp/sca/modules/eval/environment.hpp
+++ b/cpp/sca/modules/eval/environment.hpp
@@ -31,10 +31,10 @@
 #include "value.hpp"
 #include "primitive.hpp"
 
-namespace tuscany
-{
+namespace tuscany {
+namespace eval {
 
-typedef value Frame;
+typedef list<value> Frame;
 typedef list<value> Env;
 
 const value trueSymbol("true");
@@ -130,28 +130,37 @@ const value assignmentValue(const value& exp) {
     return car(cdr(cdr((list<value> )exp)));
 }
 
-const Frame addBindingToFrame(const value& var, const value& val, const Frame& frame) {
-    return cons(value(cons(var, frameVariables(frame))), cons(val, frameValues(frame)));
+const bool addBindingToFrame(const value& var, const value& val, Frame& frame) {
+    //frame = cons(value(cons(var, frameVariables(frame))), cons(val, frameValues(frame)));
+    setCar(frame, (value)cons(var, frameVariables(frame)));
+    setCdr(frame, cons(val, frameValues(frame)));
+    return true;
 }
 
-const Env defineVariable(const value& var, const value& val, Env& env) {
-    return cons(addBindingToFrame(var, val, firstFrame(env)), cdr(env));
+const bool defineVariable(const value& var, const value& val, Env& env) {
+    Frame frame = firstFrame(env);
+    addBindingToFrame(var, val, frame);
+    setCar(env, value(frame));
+    return true;
 }
 
+struct environmentReference {
+    const Env env;
+    environmentReference(const Env& env) : env(env) {
+    }
+    const Env& operator()() const {
+        return env;
+    }
+};
+
 const Env extendEnvironment(const list<value>& vars, const list<value>& vals, const Env& baseEnv) {
-//    if(length(vars) == length(vals))
-//    else if(length(vars) < length(vals))
-//        std::cout << "Too many arguments supplied " << vars << " " << vals << "\n";
-//    else
-//        std::cout << "Too few arguments supplied " << vars << " " << vals << "\n";
-//    return baseEnv;
-    return cons(makeFrame(vars, vals), baseEnv);
+    return cons(value(makeFrame(vars, vals)), lambda<list<value>()>(environmentReference(baseEnv)));
 }
 
 const Env setupEnvironment() {
     Env env = extendEnvironment(primitiveProcedureNames(), primitiveProcedureObjects(), theEmptyEnvironment());
-    env = defineVariable(trueSymbol, true, env);
-    env = defineVariable(falseSymbol, false, env);
+    defineVariable(trueSymbol, true, env);
+    defineVariable(falseSymbol, false, env);
     return env;
 }
 
@@ -178,4 +187,5 @@ const value lookupVariableValue(const value& var, const Env& env) {
 }
 
 }
+}
 #endif /* tuscany_eval_environment_hpp */
diff --git a/cpp/sca/modules/eval/eval-shell.cpp b/cpp/sca/modules/eval/eval-shell.cpp
index 46710b8354..e1c90101da 100644
--- a/cpp/sca/modules/eval/eval-shell.cpp
+++ b/cpp/sca/modules/eval/eval-shell.cpp
@@ -30,6 +30,6 @@
 #include "driver.hpp"
 
 int main() {
-    tuscany::evalDriverRun(std::cin, std::cout);
+    tuscany::eval::evalDriverRun(std::cin, std::cout);
     return 0;
 }
diff --git a/cpp/sca/modules/eval/eval-test.cpp b/cpp/sca/modules/eval/eval-test.cpp
index c536ed51a4..95a286ade0 100644
--- a/cpp/sca/modules/eval/eval-test.cpp
+++ b/cpp/sca/modules/eval/eval-test.cpp
@@ -30,6 +30,7 @@
 #include "driver.hpp"
 
 namespace tuscany {
+namespace eval {
 
 bool testEnv() {
     Env globalEnv = list<value>();
@@ -109,6 +110,11 @@ const std::string testSchemeLambda(
   "(define (testLambda) (if (= 4 (sqrt 2)) (display \"testLambda ok\") (error \"testLambda\"))) "
   "(testLambda)");
 
+const std::string testSchemeForward(
+  "(define (testLambda) (if (= 4 (sqrt 2)) (display \"testForward ok\") (error \"testForward\"))) "
+  "(define sqrt (lambda (x) (* x x))) "
+  "(testLambda)");
+
 bool contains(const std::string& str, const std::string& pattern) {
     return str.find(pattern) != str.npos;
 }
@@ -129,13 +135,14 @@ bool testEval() {
     assert(contains(evalOutput(testSchemeBegin), "testBegin1 ok"));
     assert(contains(evalOutput(testSchemeBegin), "testBegin2 ok"));
     assert(contains(evalOutput(testSchemeLambda), "testLambda ok"));
+    //assert(contains(evalOutput(testSchemeForward), "testForward ok"));
     return true;
 }
 
 bool testEvalExpr() {
     const value exp = mklist<value>("+", 2, 3);
     Env env = setupEnvironment();
-    const value r = eval(exp, env);
+    const value r = evalApply(exp, env);
     assert(r == value(5));
     return true;
 }
@@ -160,16 +167,17 @@ bool testEvalRun() {
 }
 
 }
+}
 
 int main() {
     std::cout << "Testing..." << std::endl;
 
-    tuscany::testEnv();
-    tuscany::testEnvGC();
-    tuscany::testRead();
-    tuscany::testEval();
-    tuscany::testEvalExpr();
-    tuscany::testEvalGC();
+    tuscany::eval::testEnv();
+    tuscany::eval::testEnvGC();
+    tuscany::eval::testRead();
+    tuscany::eval::testEval();
+    tuscany::eval::testEvalExpr();
+    tuscany::eval::testEvalGC();
 
     std::cout << "OK" << std::endl;
     return 0;
diff --git a/cpp/sca/modules/eval/eval.hpp b/cpp/sca/modules/eval/eval.hpp
index 2be2894bf3..1496c3bd09 100644
--- a/cpp/sca/modules/eval/eval.hpp
+++ b/cpp/sca/modules/eval/eval.hpp
@@ -33,10 +33,10 @@
 #include "read.hpp"
 #include "environment.hpp"
 
-namespace tuscany
-{
+namespace tuscany {
+namespace eval {
 
-const value eval(const value& exp, Env& env);
+const value evalApply(const value& exp, Env& env);
 
 const value compoundProcedureSymbol("compound-procedure");
 const value procedureSymbol("procedure");
@@ -89,7 +89,7 @@ const list<value> operands(const value& exp) {
 const list<value> listOfValues(const list<value> exps, Env& env) {
     if(isNil(exps))
         return list<value> ();
-    return cons(eval(car(exps), env), listOfValues(cdr(exps), env));
+    return cons(evalApply(car(exps), env), listOfValues(cdr(exps), env));
 }
 
 const value applyOperat(const value& exp) {
@@ -134,8 +134,8 @@ const value makeBegin(const list<value> seq) {
 
 const value evalSequence(const list<value>& exps, Env& env) {
     if(isLastExp(exps))
-        return eval(firstExp(exps), env);
-    eval(firstExp(exps), env);
+        return evalApply(firstExp(exps), env);
+    evalApply(firstExp(exps), env);
     return evalSequence(restExp(exps), env);
 }
 
@@ -219,17 +219,17 @@ value condToIf(const value& exp) {
 }
 
 value evalIf(const value& exp, Env& env) {
-    if(isTrue(eval(ifPredicate(exp), env)))
-        return eval(ifConsequent(exp), env);
-    return eval(ifAlternative(exp), env);
+    if(isTrue(evalApply(ifPredicate(exp), env)))
+        return evalApply(ifConsequent(exp), env);
+    return evalApply(ifAlternative(exp), env);
 }
 
 const value evalDefinition(const value& exp, Env& env) {
-    env = defineVariable(definitionVariable(exp), eval(definitionValue(exp), env), env);
+    defineVariable(definitionVariable(exp), evalApply(definitionValue(exp), env), env);
     return definitionVariable(exp);
 }
 
-const value eval(const value& exp, Env& env) {
+const value evalApply(const value& exp, Env& env) {
     if(isSelfEvaluating(exp))
         return exp;
     if(isQuoted(exp))
@@ -241,22 +241,23 @@ const value eval(const value& exp, Env& env) {
     if(isBegin(exp))
         return evalSequence(beginActions(exp), env);
     if(isCond(exp))
-        return eval(condToIf(exp), env);
+        return evalApply(condToIf(exp), env);
     if(isLambda(exp))
         return makeProcedure(lambdaParameters(exp), lambdaBody(exp), env);
     if(isVariable(exp))
         return lookupVariableValue(exp, env);
     if(isApply(exp)) {
-        list<value> applyOperandValues = eval(applyOperand(exp), env);
-        return applyProcedure(eval(applyOperat(exp), env), applyOperandValues);
+        list<value> applyOperandValues = evalApply(applyOperand(exp), env);
+        return applyProcedure(evalApply(applyOperat(exp), env), applyOperandValues);
     }
     if(isApplication(exp)) {
         list<value> operandValues = listOfValues(operands(exp), env);
-        return applyProcedure(eval(operat(exp), env), operandValues);
+        return applyProcedure(evalApply(operat(exp), env), operandValues);
     }
     std::cout << "Unknown expression type " << exp << "\n";
     return value();
 }
 
 }
+}
 #endif /* tuscany_eval_eval_hpp */
diff --git a/cpp/sca/modules/eval/primitive.hpp b/cpp/sca/modules/eval/primitive.hpp
index 0d738d1392..4ca6ea900a 100644
--- a/cpp/sca/modules/eval/primitive.hpp
+++ b/cpp/sca/modules/eval/primitive.hpp
@@ -31,8 +31,8 @@
 #include "list.hpp"
 #include "value.hpp"
 
-namespace tuscany
-{
+namespace tuscany {
+namespace eval {
 
 const value primitiveSymbol("primitive");
 const value quoteSymbol("'");
@@ -190,4 +190,5 @@ const value makeLambda(const list<value>& parameters, const list<value>& body) {
 }
 
 }
+}
 #endif /* tuscany_eval_primitive_hpp */
diff --git a/cpp/sca/modules/eval/read.hpp b/cpp/sca/modules/eval/read.hpp
index 189075ded9..994462f145 100644
--- a/cpp/sca/modules/eval/read.hpp
+++ b/cpp/sca/modules/eval/read.hpp
@@ -35,8 +35,8 @@
 #include "value.hpp"
 #include "primitive.hpp"
 
-namespace tuscany
-{
+namespace tuscany {
+namespace eval {
 
 const value rightParenthesis(mklist<value>(")"));
 const value leftParenthesis(mklist<value>("("));
@@ -180,4 +180,5 @@ const value read(std::istream& in) {
 }
 
 }
+}
 #endif /* tuscany_eval_read_hpp */