From 903c8fd49d8426ae126bb1e95c09d7ed0d4efe5b Mon Sep 17 00:00:00 2001
From: VaclavT <vaclavt@gmail.com>
Date: Tue, 2 Mar 2021 23:13:05 +0100
Subject: [PATCH] error description less verbose, some params checking added,
 comments

---
 ml.cpp | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/ml.cpp b/ml.cpp
index 14a8f1f..fe9ba00 100644
--- a/ml.cpp
+++ b/ml.cpp
@@ -635,7 +635,8 @@ MlError::~MlError() {
 }
 
 std::string MlError::description() {
-	return "error: the expression `" + cause->debug() + "` failed in scope " + to_string(env) + " with message \"" + msg + "\"";
+	// return "error: the expression `" + cause->debug() + "` failed in scope " + to_string(env) + " with message \"" + msg + "\"";
+	return "error: the expression `" + cause->debug() + "` with message \"" + msg + "\"";
 }
 
 void MlEnvironment::combine(MlEnvironment const &other) {
@@ -1088,9 +1089,9 @@ namespace builtin {
 	    HttpClient client;
 
 	    if (args.size() == 2) {
-		    for (const auto &pair_list: args[1].as_list()[0].as_list()) {
+		    for (const auto &hdr_val_pair: args[1].as_list()) {
 			    // TODO check its 2 string elements list
-			    const auto &pair = pair_list.as_list();
+			    const auto &pair = hdr_val_pair.as_list();
 			    headers[pair[0].as_string()] = pair[1].as_string();
 		    }
 	    }
@@ -1462,6 +1463,7 @@ namespace builtin {
 
 	    if (args.size() != 1)
 		    throw MlError(MlValue("head", head), env, args.size() > 1 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+
 	    std::vector<MlValue> list = args[0].as_list();
 	    if (list.empty())
 		    throw MlError(MlValue("head", head), env, INDEX_OUT_OF_RANGE);
@@ -1551,6 +1553,9 @@ namespace builtin {
     MlValue map_list(std::vector<MlValue> args, MlEnvironment &env) {
 	    eval_args(args, env);
 
+	    if (args.size() != 2)
+		    throw MlError(MlValue("map_list", map_list), env, args.size() > 2 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+
 	    std::vector<MlValue> result, l = args[1].as_list(), tmp;
 	    for (size_t i = 0; i < l.size(); i++) {
 		    tmp.push_back(l[i]);
@@ -1565,6 +1570,9 @@ namespace builtin {
     MlValue filter_list(std::vector<MlValue> args, MlEnvironment &env) {
 	    eval_args(args, env);
 
+	    if (args.size() != 2)
+		    throw MlError(MlValue("filter_list", filter_list), env, args.size() > 2 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+
 	    std::vector<MlValue> result, l = args[1].as_list(), tmp;
 	    for (size_t i = 0; i < l.size(); i++) {
 		    tmp.push_back(l[i]);
@@ -1575,9 +1583,14 @@ namespace builtin {
 	    return MlValue(result);
     }
 
+	// >>> (reduce (lambda (x y) (+ (* x 10) y)) 0 '(1 2 3 4))
+	//  => 1234
     MlValue reduce_list(std::vector<MlValue> args, MlEnvironment &env) {
 	    eval_args(args, env);
 
+	    if (args.size() != 3)
+		    throw MlError(MlValue("reduce_list", reduce_list), env, args.size() > 3 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+
 	    std::vector<MlValue> l = args[2].as_list(), tmp;
 	    MlValue acc = args[1];
 	    for (size_t i = 0; i < l.size(); i++) {
@@ -1589,9 +1602,14 @@ namespace builtin {
 	    return acc;
     }
 
+	// >>> (range 1 5)
+	//  => (1 2 3 4)
     MlValue range(std::vector<MlValue> args, MlEnvironment &env) {
 	    eval_args(args, env);
 
+	    if (args.size() != 2)
+		    throw MlError(MlValue("range", range), env, args.size() > 2 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+
 	    std::vector<MlValue> result;
 	    MlValue low = args[0], high = args[1];
 	    if (low.get_type_name() != INT_TYPE && low.get_type_name() != FLOAT_TYPE)
@@ -1782,7 +1800,7 @@ int main(int argc, const char **argv) {
 	try {
 		load_std_lib(env);
         // for xcode profiling
-        run(read_file_contents("/Users/vaclavt/Development/mlisp/tests/test.lsp"), env);
+        // run(read_file_contents("/Users/vaclavt/Development/mlisp/tests/test.lsp"), env);
 
 		if (argc == 1 || (argc == 2 && std::string(argv[1]) == "-i"))
 			repl(env);