added 2 code files; added enl instruction; completed main to do the right thing

code/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.txt

@@ -0,0 +1,4 @@
+\avans-minor-swa-cpp1
+rot
+\.txt
+cat

code/ninaf-zvabe-fjn-pcc1.txt

@@ -0,0 +1,31 @@
+\Erny fghcvqvgl orngf negvsvpvny vagryyvtrapr rirel gvzr.
+rot
+enl
+=quote
+\ !
+0
+1
+slc
+=space
+$space
+=white
+37
+=cnt
+:loop
+$space
+$white
+cat
+=space
+$cnt
+dec
+=cnt
+$cnt
+0
+>loop
+gne
+$quote
+$space
+cat
+\-- Terry Pratchett
+cat
+end

code/start.txt

@@ -15,4 +15,5 @@ $ctr
 >loop
 gne
 $result
-end
+\.txt
+cat

interpreter.cpp

@@ -119,6 +119,7 @@ void interpreter::exec_instruction(const std::string& code, bool& done) {
     else if (code == "gge") gge();
     else if (code == "fun") fun();
     else if (code == "ret") ret();
+    else if (code == "enl") enl();
     else throw syntax_error {code};
 }
 
@@ -271,6 +272,14 @@ void interpreter::rot() {
     _pc++;
 }
 
+void interpreter::enl() {
+    std::string val {_stack.back()};
+    _stack.pop_back();
+    val += '\n';
+    _stack.push_back(val);
+    _pc++;
+}
+
 // tests & jumps ----------------------------------------------------------
 
 void interpreter::gto() {

interpreter.hpp

@@ -57,6 +57,7 @@ class interpreter {
         void cat();
         void len();
         void rot();
+        void enl();
 
         // tests & jumps
         void gto();

main.cpp

@@ -74,7 +74,7 @@ int main(int argc, const char * argv[]) {
         interpreter proc;
         while (!done) {
             code = req.get(base_url + next_url);
-            std::cerr << code << '\n';
+            // std::cerr << code << '\n';
             std::istringstream in {code};
             next_url = proc.eval(in, done);
             std::cerr << next_url << '\n';