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+//: Some instructions can take string literals for convenience.
+//:
+//: Instead of quotes, we'll use [] to delimit strings. That'll reduce the
+//: need for escaping since we can support nested brackets. And we can also
+//: imagine that 'recipe' might one day itself be defined in mu, doing its own
+//: parsing.
+
+//: First extend the mu parser to support string literals.
+:(scenario "string_literal")
+recipe main [
+  1:address:array:character <- new [abc def]
+]
++parse:   ingredient: {name: "abc def", value: 0, type: 0, properties: ["abc def": "literal-string"]}
+
+:(scenario "string_literal_with_colons")
+recipe main [
+  1:address:array:character <- new [abc:def/ghi]
+]
++parse:   ingredient: {name: "abc:def/ghi", value: 0, type: 0, properties: ["abc:def/ghi": "literal-string"]}
+
+:(before "End Mu Types Initialization")
+Type_number["literal-string"] = 0;
+
+:(after "string next_word(istream& in)")
+if (in.peek() == '[') return slurp_quoted(in);
+
+:(code)
+string slurp_quoted(istream& in) {
+  assert(!in.eof());
+  assert(in.peek() == '[');
+  ostringstream out;
+  int size = 0;
+  while (!in.eof()) {
+    char c = in.get();
+//?     cout << c << '\n'; //? 1
+    out << c;
+//?     cout << out.str() << "$\n"; //? 1
+    if (c == '[') ++size;
+    if (c == ']') --size;
+    if (size == 0) break;
+  }
+  return out.str();
+}
+
+:(after "reagent::reagent(string s)")
+//?   cout << s[0] << '\n'; //? 1
+  if (s[0] == '[') {
+    assert(s[s.size()-1] == ']');
+    // delete [] delimiters
+    s.erase(0, 1);
+    s.erase(s.size()-1, s.size());
+    name = s;
+    types.push_back(0);
+    properties.push_back(pair<string, vector<string> >(name, vector<string>()));
+    properties.back().second.push_back("literal-string");
+    return;
+  }
+
+:(scenario "string_literal_nested")
+recipe main [
+  1:address:array:character <- new [abc [def]]
+]
++parse:   ingredient: {name: "abc [def]", value: 0, type: 0, properties: ["abc [def]": "literal-string"]}
+
+//: Next, extend 'new' to handle a string literal argument.
+:(scenario "new_string")
+recipe main [
+  1:address:array:character <- new [abc def]
+  2:character <- index 1:address:array:character/deref, 5:literal
+]
+# integer code for 'e'
++mem: storing 101 in location 2
+
+:(before "End Mu Types Initialization")
+Type_number["character"] = Next_type_number++;
+
+:(after "case NEW" following "Primitive Recipe Implementations")
+if (instructions[pc].ingredients[0].properties[0].second[0] == "literal-string") {
+  // allocate an array just large enough for it
+  vector<int> result;
+  result.push_back(Current_routine->alloc);
+  write_memory(instructions[pc].products[0], result);
+  // assume that all characters fit in a single location
+//?   cout << "new string literal: " << instructions[pc].ingredients[0].name << '\n'; //? 1
+  Memory[Current_routine->alloc++] = instructions[pc].ingredients[0].name.size();
+  for (size_t i = 0; i < instructions[pc].ingredients[0].name.size(); ++i) {
+    Memory[Current_routine->alloc++] = instructions[pc].ingredients[0].name[i];
+  }
+  // mu strings are not null-terminated in memory
+  break;
+}