//: A program is a book of 'recipes' (functions) :(before "End Globals") //: Each recipe is stored at a specific page number, or ordinal. map Recipe; //: You can also refer to each recipe by its name. map Recipe_ordinal; recipe_ordinal Next_recipe_ordinal = 1; //: Ordinals are like numbers, except you can't do arithmetic on them. Ordinal //: 1 is not less than 2, it's just different. Phone numbers are ordinals; //: adding two phone numbers is meaningless. Here each recipe does something //: incommensurable with any other recipe. :(after "Types") typedef int recipe_ordinal; :(before "End Types") // Recipes are lists of instructions. To perform or 'run' a recipe, the // computer runs its instructions. struct recipe { string name; vector steps; // End recipe Fields recipe(); }; :(before "struct recipe") // Each instruction is either of the form: // product1, product2, product3, ... <- operation ingredient1, ingredient2, ingredient3, ... // or just a single 'label' starting with a non-alphanumeric character // +label // Labels don't do anything, they're just waypoints. struct instruction { bool is_label; string label; // only if is_label string name; // only if !is_label string old_name; // before our automatic rewrite rules string original_string; // for error messages recipe_ordinal operation; // get(Recipe_ordinal, name) vector ingredients; // only if !is_label vector products; // only if !is_label // End instruction Fields instruction(); void clear(); bool is_empty(); }; :(before "struct instruction") // Ingredients and products are a single species -- a reagent. Reagents refer // either to numbers or to locations in memory along with 'type' tags telling // us how to interpret them. They also can contain arbitrary other lists of // properties besides types, but we're getting ahead of ourselves. struct reagent { string original_string; string name; type_tree* type; vector > properties; // can't be a map because the string_tree sometimes needs to be NULL, which can be confusing double value; bool initialized; // End reagent Fields reagent(const string& s); reagent() :type(NULL), value(0), initialized(false) {} ~reagent(); void clear(); reagent(const reagent& old); reagent& operator=(const reagent& old); void set_value(double v) { value = v; initialized = true; } }; :(before "struct reagent") // Types can range from a simple type ordinal, to arbitrarily complex trees of // type parameters, like (map (address array character) (list number)) struct type_tree { string name; type_ordinal value; type_tree* left; type_tree* right; ~type_tree(); type_tree(const type_tree& old); // simple: type ordinal explicit type_tree(string name); type_tree(string name, type_ordinal v) :name(name), value(v), left(NULL), right(NULL) {} // intermediate: list of type ordinals type_tree(string name, type_ordinal v, type_tree* r) :name(name), value(v), left(NULL), right(r) {} type_tree(string name, type_tree* r); // advanced: tree containing type ordinals type_tree(type_tree* l, type_tree* r) :value(0), left(l), right(r) {} }; struct string_tree { string value; string_tree* left; string_tree* right; ~string_tree(); string_tree(const string_tree& old); // simple: flat string explicit string_tree(string v) :value(v), left(NULL), right(NULL) {} // intermediate: list of strings string_tree(string v, string_tree* r) :value(v), left(NULL), right(r) {} // advanced: tree containing strings string_tree(string_tree* l, string_tree* r) :left(l), right(r) {} }; // End type_tree Definition :(code) type_tree::type_tree(string name) :name(name), value(get(Type_ordinal, name)), left(NULL), right(NULL) {} type_tree::type_tree(string name, type_tree* r) :name(name), value(get(Type_ordinal, name)), left(NULL), right(r) {} :(before "End Globals") // Locations refer to a common 'memory'. Each location can store a number. map Memory; :(before "End Setup") Memory.clear(); :(after "Types") // Mu types encode how the numbers stored in different parts of memory are // interpreted. A location tagged as a 'character' type will interpret the // value 97 as the letter 'a', while a different location of type 'number' // would not. // // Unlike most computers today, mu stores types in a single big table, shared // by all the mu programs on the computer. This is useful in providing a // seamless experience to help understand arbitrary mu programs. typedef int type_ordinal; :(before "End Globals") map Type_ordinal; map Type; type_ordinal Next_type_ordinal = 1; :(code) void setup_types() { Type.clear(); Type_ordinal.clear(); put(Type_ordinal, "literal", 0); Next_type_ordinal = 1; // Mu Types Initialization type_ordinal number = put(Type_ordinal, "number", Next_type_ordinal++); get_or_insert(Type, number).name = "number"; put(Type_ordinal, "location", number); // synonym of number to indicate we only care about its size type_ordinal address = put(Type_ordinal, "address", Next_type_ordinal++); get_or_insert(Type, address).name = "address"; type_ordinal boolean = put(Type_ordinal, "boolean", Next_type_ordinal++); get_or_insert(Type, boolean).name = "boolean"; type_ordinal character = put(Type_ordinal, "character", Next_type_ordinal++); get_or_insert(Type, character).name = "character"; // Array types are a special modifier to any other type. For example, // array:number or array:address:boolean. type_ordinal array = put(Type_ordinal, "array", Next_type_ordinal++); get_or_insert(Type, array).name = "array"; // End Mu Types Initialization } void teardown_types() { for (map::iterator p = Type.begin(); p != Type.end(); ++p) { for (int i = 0; i < SIZE(p->second.elements); ++i) p->second.elements.clear(); } Type_ordinal.clear(); } :(before "End One-time Setup") setup_types(); atexit(teardown_types); :(before "End Types") // You can construct arbitrary new types. New types are either 'containers' // with multiple 'elements' of other types, or 'exclusive containers' containing // one of multiple 'variants'. (These are similar to C structs and unions, // respectively, though exclusive containers implicitly include a tag element // recording which variant they should be interpreted as.) // // For example, storing bank balance and name for an account might require a // container, but if bank accounts may be either for individuals or groups, // with different properties for each, that may require an exclusive container // whose variants are individual-account and joint-account containers. enum kind_of_type { PRIMITIVE, CONTAINER, EXCLUSIVE_CONTAINER }; struct type_info { string name; kind_of_type kind; vector elements; // End type_info Fields type_info() :kind(PRIMITIVE) { // End type_info Constructor } }; enum primitive_recipes { IDLE = 0, COPY, // End Primitive Recipe Declarations MAX_PRIMITIVE_RECIPES, }; :(code) //: It's all very well to construct recipes out of other recipes, but we need //: to know how to do *something* out of the box. For the following //: recipes there are only codes, no entries in the book, because mu just knows //: what to do for them. void setup_recipes() { Recipe.clear(); Recipe_ordinal.clear(); put(Recipe_ordinal, "idle", IDLE); // Primitive Recipe Numbers put(Recipe_ordinal, "copy", COPY); // End Primitive Recipe Numbers } //: We could just reset the recipe table after every test, but that gets slow //: all too quickly. Instead, initialize the common stuff just once at //: startup. Later layers will carefully undo each test's additions after //: itself. :(before "End One-time Setup") setup_recipes(); assert(MAX_PRIMITIVE_RECIPES < 200); // level 0 is primitives; until 199 Next_recipe_ordinal = 200; put(Recipe_ordinal, "main", Next_recipe_ordinal++); // End Load Recipes :(before "End Commandline Parsing") assert(Next_recipe_ordinal < 1000); // recipes being tested didn't overflow into test space :(before "End Setup") Next_recipe_ordinal = 1000; // consistent new numbers for each test //: One final detail: tests can modify our global tables of recipes and types, //: so we need some way to clean up after each test is done so it doesn't //: influence later ones. :(before "End Globals") map Recipe_ordinal_snapshot; map Recipe_snapshot; map Type_ordinal_snapshot; map Type_snapshot; :(before "End One-time Setup") save_snapshots(); :(before "End Setup") restore_snapshots(); :(code) void save_snapshots() { Recipe_ordinal_snapshot = Recipe_ordinal; Recipe_snapshot = Recipe; Type_ordinal_snapshot = Type_ordinal; Type_snapshot = Type; // End save_snapshots } void restore_snapshots() { Recipe = Recipe_snapshot; Recipe_ordinal = Recipe_ordinal_snapshot; Type_ordinal = Type_ordinal_snapshot; Type = Type_snapshot; // End restore_snapshots } //:: Helpers :(code) recipe::recipe() { // End recipe Constructor } instruction::instruction() :is_label(false), operation(IDLE) { // End instruction Constructor } void instruction::clear() { is_label=false; label.clear(); name.clear(); old_name.clear(); operation=IDLE; ingredients.clear(); products.clear(); original_string.clear(); } bool instruction::is_empty() { return !is_label && name.empty(); } // Reagents have the form :::...///... reagent::reagent(const string& s) :original_string(s), type(NULL), value(0), initialized(false) { // Parsing reagent(string s) istringstream in(s); in >> std::noskipws; // name and type istringstream first_row(slurp_until(in, '/')); first_row >> std::noskipws; name = slurp_until(first_row, ':'); string_tree* type_names = parse_property_list(first_row); // End Parsing Reagent Type Property(type_names) type = new_type_tree(type_names); delete type_names; // special cases if (is_integer(name) && type == NULL) type = new type_tree("literal"); if (name == "_" && type == NULL) type = new type_tree("literal"); // other properties slurp_properties(in, properties); // End Parsing reagent } void slurp_properties(istream& in, vector >& out) { while (has_data(in)) { istringstream row(slurp_until(in, '/')); row >> std::noskipws; string key = slurp_until(row, ':'); string_tree* value = parse_property_list(row); out.push_back(pair(key, value)); } } string_tree* parse_property_list(istream& in) { skip_whitespace_but_not_newline(in); if (!has_data(in)) return NULL; string_tree* result = new string_tree(slurp_until(in, ':')); result->right = parse_property_list(in); return result; } type_tree* new_type_tree(const string_tree* properties) { if (!properties) return NULL; type_tree* result = new type_tree("", 0); if (!properties->value.empty()) { const string& type_name = result->name = properties->value; if (contains_key(Type_ordinal, type_name)) result->value = get(Type_ordinal, type_name); else if (is_integer(type_name)) // sometimes types will contain non-type tags, like numbers for the size of an array result->value = 0; else if (properties->value != "->") // used in recipe types result->value = -1; // should never happen; will trigger errors later } result->left = new_type_tree(properties->left); result->right = new_type_tree(properties->right); return result; } //: avoid memory leaks for the type tree reagent::reagent(const reagent& other) { original_string = other.original_string; name = other.name; value = other.value; initialized = other.initialized; for (int i = 0; i < SIZE(other.properties); ++i) { properties.push_back(pair(other.properties.at(i).first, other.properties.at(i).second ? new string_tree(*other.properties.at(i).second) : NULL)); } type = other.type ? new type_tree(*other.type) : NULL; // End reagent Copy Constructor } type_tree::type_tree(const type_tree& old) { name = old.name; value = old.value; left = old.left ? new type_tree(*old.left) : NULL; right = old.right ? new type_tree(*old.right) : NULL; } string_tree::string_tree(const string_tree& old) { value = old.value; left = old.left ? new string_tree(*old.left) : NULL; right = old.right ? new string_tree(*old.right) : NULL; } reagent& reagent::operator=(const reagent& other) { original_string = other.original_string; for (int i = 0; i < SIZE(properties); ++i) if (properties.at(i).second) delete properties.at(i).second; properties.clear(); for (int i = 0; i < SIZE(other.properties); ++i) properties.push_back(pair(other.properties.at(i).first, other.properties.at(i).second ? new string_tree(*other.properties.at(i).second) : NULL)); name = other.name; value = other.value; initialized = other.initialized; if (type) delete type; type = other.type ? new type_tree(*other.type) : NULL; // End reagent Copy Operator return *this; } reagent::~reagent() { clear(); } void reagent::clear() { for (int i = 0; i < SIZE(properties); ++i) { if (properties.at(i).second) { delete properties.at(i).second; properties.at(i).second = NULL; } } delete type; type = NULL; } type_tree::~type_tree() { delete left; delete right; } string_tree::~string_tree() { delete left; delete right; } void append(type_tree*& base, type_tree* extra) { if (!base) { base = extra; return; } type_tree* curr = base; while (curr->right) curr = curr->right; curr->right = extra; } void append(string_tree*& base, string_tree* extra) { if (!base) { base = extra; return; } string_tree* curr = base; while (curr->right) curr = curr->right; curr->right = extra; } string slurp_until(istream& in, char delim) { ostringstream out; char c; while (in >> c) { if (c == delim) { // drop the delim break; } out << c; } return out.str(); } bool has_property(const reagent& x, const string& name) { for (int i = 0; i < SIZE(x.properties); ++i) { if (x.properties.at(i).first == name) return true; } return false; } string_tree* property(const reagent& r, const string& name) { for (int p = 0; p != SIZE(r.properties); ++p) { if (r.properties.at(p).first == name) return r.properties.at(p).second; } return NULL; } :(before "End Globals") extern const string Ignore(","); // commas are ignored in mu except within [] strings :(code) void skip_whitespace_but_not_newline(istream& in) { while (true) { if (!has_data(in)) break; else if (in.peek() == '\n') break; else if (isspace(in.peek())) in.get(); else if (Ignore.find(in.peek()) != string::npos) in.get(); else break; } } void dump_memory() { for (map::iterator p = Memory.begin(); p != Memory.end(); ++p) { cout << p->first << ": " << no_scientific(p->second) << '\n'; } } //:: Helpers for converting various values to string //: Use to_string() in trace(), and try to keep it stable from run to run. //: Use debug_string() while debugging, and throw everything into it. //: Use inspect() only for emitting a canonical format that can be parsed back //: into the value. string to_string(const recipe& r) { ostringstream out; out << "recipe " << r.name << " [\n"; for (int i = 0; i < SIZE(r.steps); ++i) out << " " << to_string(r.steps.at(i)) << '\n'; out << "]\n"; return out.str(); } string debug_string(const recipe& x) { ostringstream out; out << "- recipe " << x.name << '\n'; // Begin debug_string(recipe x) for (int index = 0; index < SIZE(x.steps); ++index) { const instruction& inst = x.steps.at(index); out << "inst: " << to_string(inst) << '\n'; out << " ingredients\n"; for (int i = 0; i < SIZE(inst.ingredients); ++i) out << " " << debug_string(inst.ingredients.at(i)) << '\n'; out << " products\n"; for (int i = 0; i < SIZE(inst.products); ++i) out << " " << debug_string(inst.products.at(i)) << '\n'; } return out.str(); } string to_original_string(const instruction& inst) { if (inst.is_label) return inst.label; ostringstream out; for (int i = 0; i < SIZE(inst.products); ++i) { if (i > 0) out << ", "; out << inst.products.at(i).original_string; } if (!inst.products.empty()) out << " <- "; out << inst.name << ' '; for (int i = 0; i < SIZE(inst.ingredients); ++i) { if (i > 0) out << ", "; out << inst.ingredients.at(i).original_string; } return out.str(); } string to_string(const instruction& inst) { if (inst.is_label) return inst.label; ostringstream out; for (int i = 0; i < SIZE(inst.products); ++i) { if (i > 0) out << ", "; out << to_string(inst.products.at(i)); } if (!inst.products.empty()) out << " <- "; out << inst.name << ' '; for (int i = 0; i < SIZE(inst.ingredients); ++i) { if (i > 0) out << ", "; out << to_string(inst.ingredients.at(i)); } return out.str(); } string to_string(const reagent& r) { if (is_dummy(r)) return "_"; ostringstream out; out << "{"; out << r.name << ": " << names_to_string(r.type); if (!r.properties.empty()) { for (int i = 0; i < SIZE(r.properties); ++i) out << ", \"" << r.properties.at(i).first << "\": " << to_string(r.properties.at(i).second); } out << "}"; return out.str(); } // special name for ignoring some products bool is_dummy(const reagent& x) { return x.name == "_"; } string debug_string(const reagent& x) { ostringstream out; out << x.name << ": " << x.value << ' ' << to_string(x.type) << " -- " << to_string(x); return out.str(); } string to_string(const string_tree* property) { if (!property) return "()"; ostringstream out; if (!property->left && !property->right) // abbreviate a single-node tree to just its contents out << '"' << property->value << '"'; else dump(property, out); return out.str(); } void dump(const string_tree* x, ostream& out) { if (!x->left && !x->right) { out << x->value; return; } out << '('; for (const string_tree* curr = x; curr; curr = curr->right) { if (curr != x) out << ' '; if (curr->left) dump(curr->left, out); else out << '"' << curr->value << '"'; } out << ')'; } string to_string(const type_tree* type) { // abbreviate a single-node tree to just its contents if (!type) return "NULLNULLNULL"; // should never happen ostringstream out; dump(type, out); return out.str(); } void dump(const type_tree* x, ostream& out) { if (!x->left && !x->right) { dump(x->value, out); return; } out << '('; for (const type_tree* curr = x; curr; curr = curr->right) { if (curr != x) out << ' '; if (curr->left) dump(curr->left, out); else dump(curr->value, out); } out << ')'; } void dump(type_ordinal type, ostream& out) { if (contains_key(Type, type)) out << get(Type, type).name; else out << "?" << type; } string names_to_string(const type_tree* type) { // abbreviate a single-node tree to just its contents if (!type) return "()"; // should never happen ostringstream out; dump_names(type, out); return out.str(); } void dump_names(const type_tree* type, ostream& out) { if (!type->left && !type->right) { out << '"' << type->name << '"'; return; } out << '('; for (const type_tree* curr = type; curr; curr = curr->right) { if (curr != type) out << ' '; if (curr->left) dump_names(curr->left, out); else out << '"' << curr->name << '"'; } out << ')'; } string names_to_string_without_quotes(const type_tree* type) { // abbreviate a single-node tree to just its contents if (!type) return "NULLNULLNULL"; // should never happen ostringstream out; dump_names_without_quotes(type, out); return out.str(); } void dump_names_without_quotes(const type_tree* type, ostream& out) { if (!type->left && !type->right) { out << type->name; return; } out << '('; for (const type_tree* curr = type; curr; curr = curr->right) { if (curr != type) out << ' '; if (curr->left) dump_names_without_quotes(curr->left, out); else out << curr->name; } out << ')'; } //: helper to print numbers without excessive precision :(before "End Types") struct no_scientific { double x; explicit no_scientific(double y) :x(y) {} }; :(code) ostream& operator<<(ostream& os, no_scientific x) { if (!isfinite(x.x)) { // Infinity or NaN os << x.x; return os; } ostringstream tmp; tmp << std::fixed << x.x; os << trim_floating_point(tmp.str()); return os; } string trim_floating_point(const string& in) { if (in.empty()) return ""; int length = SIZE(in); while (length > 1) { if (in.at(length-1) != '0') break; --length; } if (in.at(length-1) == '.') --length; return in.substr(0, length); } void test_trim_floating_point() { CHECK_EQ("", trim_floating_point("")); CHECK_EQ("0", trim_floating_point("000000000")); CHECK_EQ("1.5", trim_floating_point("1.5000")); CHECK_EQ("1.000001", trim_floating_point("1.000001")); CHECK_EQ("23", trim_floating_point("23.000000")); CHECK_EQ("23", trim_floating_point("23.0")); CHECK_EQ("23", trim_floating_point("23.")); CHECK_EQ("23", trim_floating_point("23")); CHECK_EQ("3", trim_floating_point("3.000000")); CHECK_EQ("3", trim_floating_point("3.0")); CHECK_EQ("3", trim_floating_point("3.")); CHECK_EQ("3", trim_floating_point("3")); } :(before "End Includes") #include using std::pair; #include