4302 - a more elaborate pass-through phase

Starting to work out the skeleton every phase needs to have.

2 files changed, 35 insertions, 3 deletions

diff --git a/subx/010core.cc b/subx/010core.cc
index f391a369..f8dcdf20 100644
--- a/subx/010core.cc
+++ b/subx/010core.cc
@@ -100,6 +100,7 @@ End_of_program = 0;
 // of its bytes, and run it
 void run(string text_bytes) {
   // Begin run() For Scenarios
+  cerr << text_bytes << '\n';
   load_program(text_bytes, 1);  // tests always assume a starting address of 1
   EIP = 1;  // preserve null pointer
   while (EIP < End_of_program)
diff --git a/subx/022transform_immediate.cc b/subx/022transform_immediate.cc
index 24a61f68..65ff95ce 100644
--- a/subx/022transform_immediate.cc
+++ b/subx/022transform_immediate.cc
@@ -1,8 +1,39 @@
 :(before "End One-time Setup")
-Transform.push_back(identity);
+Transform.push_back(skip_whitespace_and_comments);
 
 :(code)
-void identity(const string& input, string& output) {
+void skip_whitespace_and_comments(const string& input, string& output) {
   cerr << "running compiler phase\n";
-  output = input;
+  istringstream in(input);
+  in >> std::noskipws;
+  ostringstream out;
+  while (has_data(in)) {
+    string word = next_word(in);
+    out << word << ' ';
+  }
+  out.str().swap(output);
+}
+
+string next_word(istream& in) {
+  skip_whitespace_and_comments(in);
+  string result;
+  in >> result;
+  return result;
+}
+
+void skip_whitespace_and_comments(istream& in) {
+  while (true) {
+    char c = in.peek();
+    if (isspace(c)) { in.get();  continue; }
+    else if (c == '#') skip_comment(in);
+    else return;
+  }
+}
+
+void skip_comment(istream& in) {
+  assert(in.peek() == '#');
+  char c = '\0';
+  do {
+    in >> c;
+  } while (c != '\n');
 }