Fix macro. (#19)

BowenFu · web-flow · commit 018475ba5176 · 2021-12-17T08:30:15.000+08:00
Co-authored-by: Bowen Fu &lt;missing&gt;
diff --git a/include/lisp/evaluator.h b/include/lisp/evaluator.h
@@ -56,7 +56,7 @@ class Env
         auto iter = mFrame.find(variableName);
         if (iter == mFrame.end())
         {
-            throw std::runtime_error{"call setVariableValue to undefined variables."};
+            throw std::runtime_error{"call setVariableValue to undefined variables." + variableName};
         }
         iter->second = value;
         return value;
@@ -73,7 +73,7 @@ class Env
     {
         if (mFrame.count(variableName))
         {
-            throw std::runtime_error{"call defineVariable to defined variables."};
+            throw std::runtime_error{"call defineVariable to defined variables." + variableName};
         }
         mFrame.insert({variableName, value});
         return value;
diff --git a/include/lisp/parser.h b/include/lisp/parser.h
@@ -230,11 +230,16 @@ inline ExprPtr application(ExprPtr const& car, ExprPtr const& cdr)
     return ExprPtr{new Application(op, params)};
 }
 
-inline ExprPtr macroApplication(ExprPtr const& car, ExprPtr const& cdr)
+inline ExprPtr tryMacroApplication(ExprPtr const& car, ExprPtr const& cdr, std::shared_ptr<Env> const& env)
 {
     auto op = parse(car);
-    std::vector<ExprPtr> params = consToVec(cdr);
-    return ExprPtr{new Application(op, params)};
+    auto evaledOp = op->eval(env);
+    if (dynamic_cast<MacroProcedure const*>(evaledOp.get()))
+    {
+        std::vector<ExprPtr> params = consToVec(cdr);
+        return Application(evaledOp, params).eval(env);
+    }
+    return ExprPtr{new Cons{car, cdr}};
 }
 
 inline ExprPtr application(ExprPtr const& expr)
@@ -359,7 +364,7 @@ inline auto tryMacroCall(ExprPtr const& expr, std::shared_ptr<Env> const& env) -
     }
     if (env->variableDefined(carStr.value()))
     {
-        return macroApplication(car, cdr)->eval(env);
+        return tryMacroApplication(car, cdr, env);
     }
     return expr;
 }
@@ -472,16 +477,18 @@ void forEach(ExprPtr const& expr, Func func)
     func(expr);
 }
 
-inline void defineMacros(ExprPtr const& expr, std::shared_ptr<Env> const& env)
+inline auto defineMacros(ExprPtr const& expr, std::shared_ptr<Env> const& env) -> ExprPtr
 {
     auto func = [&env](auto const& expr)
     {
         if (auto macroDefinition = parseMacroDefinition(expr))
         {
             macroDefinition->eval(env);
+            return nil();
         }
+        return expr;
     };
-    forEach(expr, func);
+    return transform(expr, func);
 }
 
 // FIXME
diff --git a/sample/CMakeLists.txt b/sample/CMakeLists.txt
@@ -135,4 +135,7 @@ do_test(test_macro_negate_add "(define negate (macro (x) `(- ,x))) (negate (+ 1
 do_test(test_macro_double "(define double (macro (x) `(* ,x 2))) (double (+ 1 1))" "4")
 
 do_test(test_macro_show "(define show (macro (x) `(list ',x))) (show (+ 1 1))" "\\\\(\\\\'\\\\+ 1 1\\\\)")
-do_test(test_macro_first "(define first (macro (x) `(car ',x))) (first (+ 1 1))" "'+")
+do_test(test_macro_first "(define first (macro (x) `(car ',x))) (first (+ 1 1))" "'+")
+do_test(test_macro_first "(define rest (macro (x) `(cdr ',x))) (rest (+ 1 1))" "(1 1)")
+
+do_test(test_macro_first "(define replaceOp (macro (orig op) `(,op . ,(cdr orig)))) (replaceOp (+ 3 3) *)" "9")
diff --git a/sample/loop.cpp b/sample/loop.cpp
@@ -147,12 +147,13 @@ auto eval(std::string const& input, std::shared_ptr<Env> const& env)
     Lexer lex(input);
     MetaParser p(lex);
     std::string result;
-    auto macroEnv = std::make_shared<Env>();
+    // auto macroEnv = std::make_shared<Env>();
+    auto macroEnv = env;
     do
     {
         auto me = p.sexpr();
-        defineMacros(me, macroEnv);
-        auto ee = expandMacros(me, macroEnv);
+        auto de = defineMacros(me, macroEnv);
+        auto ee = expandMacros(de, macroEnv);
 #if DEBUG
         std::cout << "ee ## " << ee->toString() << std::endl; 
 #endif // DEBUG

Original file line number	Diff line number	Diff line change
`@@ -56,7 +56,7 @@ class Env`
`56`	`56`	`auto iter = mFrame.find(variableName);`
`57`	`57`	`if (iter == mFrame.end())`
`58`	`58`	`{`
`59`		`- throw std::runtime_error{"call setVariableValue to undefined variables."};`
	`59`	`+ throw std::runtime_error{"call setVariableValue to undefined variables." + variableName};`
`60`	`60`	`}`
`61`	`61`	`iter->second = value;`
`62`	`62`	`return value;`
`@@ -73,7 +73,7 @@ class Env`
`73`	`73`	`{`
`74`	`74`	`if (mFrame.count(variableName))`
`75`	`75`	`{`
`76`		`- throw std::runtime_error{"call defineVariable to defined variables."};`
	`76`	`+ throw std::runtime_error{"call defineVariable to defined variables." + variableName};`
`77`	`77`	`}`
`78`	`78`	`mFrame.insert({variableName, value});`
`79`	`79`	`return value;`
Original file line number	Diff line number	Diff line change
`@@ -230,11 +230,16 @@ inline ExprPtr application(ExprPtr const& car, ExprPtr const& cdr)`
`230`	`230`	`return ExprPtr{new Application(op, params)};`
`231`	`231`	`}`
`232`	`232`
`233`		`-inline ExprPtr macroApplication(ExprPtr const& car, ExprPtr const& cdr)`
	`233`	`+inline ExprPtr tryMacroApplication(ExprPtr const& car, ExprPtr const& cdr, std::shared_ptr<Env> const& env)`
`234`	`234`	`{`
`235`	`235`	`auto op = parse(car);`
`236`		`- std::vector<ExprPtr> params = consToVec(cdr);`
`237`		`- return ExprPtr{new Application(op, params)};`
	`236`	`+ auto evaledOp = op->eval(env);`
	`237`	`+ if (dynamic_cast<MacroProcedure const*>(evaledOp.get()))`
	`238`	`+ {`
	`239`	`+ std::vector<ExprPtr> params = consToVec(cdr);`
	`240`	`+ return Application(evaledOp, params).eval(env);`
	`241`	`+ }`
	`242`	`+ return ExprPtr{new Cons{car, cdr}};`
`238`	`243`	`}`
`239`	`244`
`240`	`245`	`inline ExprPtr application(ExprPtr const& expr)`
`@@ -359,7 +364,7 @@ inline auto tryMacroCall(ExprPtr const& expr, std::shared_ptr<Env> const& env) -`
`359`	`364`	`}`
`360`	`365`	`if (env->variableDefined(carStr.value()))`
`361`	`366`	`{`
`362`		`- return macroApplication(car, cdr)->eval(env);`
	`367`	`+ return tryMacroApplication(car, cdr, env);`
`363`	`368`	`}`
`364`	`369`	`return expr;`
`365`	`370`	`}`
`@@ -472,16 +477,18 @@ void forEach(ExprPtr const& expr, Func func)`
`472`	`477`	`func(expr);`
`473`	`478`	`}`
`474`	`479`
`475`		`-inline void defineMacros(ExprPtr const& expr, std::shared_ptr<Env> const& env)`
	`480`	`+inline auto defineMacros(ExprPtr const& expr, std::shared_ptr<Env> const& env) -> ExprPtr`
`476`	`481`	`{`
`477`	`482`	`auto func = [&env](auto const& expr)`
`478`	`483`	`{`
`479`	`484`	`if (auto macroDefinition = parseMacroDefinition(expr))`
`480`	`485`	`{`
`481`	`486`	`macroDefinition->eval(env);`
	`487`	`+ return nil();`
`482`	`488`	`}`
	`489`	`+ return expr;`
`483`	`490`	`};`
`484`		`- forEach(expr, func);`
	`491`	`+ return transform(expr, func);`
`485`	`492`	`}`
`486`	`493`
`487`	`494`	`// FIXME`