//: Containers contain a fixed number of elements of different types. :(before "End Mu Types Initialization") //: We'll use this container as a running example in scenarios below. type_ordinal point = put(Type_ordinal, "point", Next_type_ordinal++); get_or_insert(Type, point); // initialize get(Type, point).kind = CONTAINER; get(Type, point).name = "point"; get(Type, point).elements.push_back(reagent("x:number")); get(Type, point).elements.push_back(reagent("y:number")); //: Containers can be copied around with a single instruction just like //: numbers, no matter how large they are. //: Tests in this layer often explicitly set up memory before reading it as a //: container. Don't do this in general. I'm tagging such cases with /unsafe; //: they'll be exceptions to later checks. :(scenario copy_multiple_locations) def main [ 1:num <- copy 34 2:num <- copy 35 3:point <- copy 1:point/unsafe ] +mem: storing 34 in location 3 +mem: storing 35 in location 4 //: trying to copy to a differently-typed destination will fail :(scenario copy_checks_size) % Hide_errors = true; def main [ 2:point <- copy 1:num ] +error: main: can't copy '1:num' to '2:point'; types don't match :(before "End Mu Types Initialization") // A more complex example container, containing another container as one of // its elements. type_ordinal point_number = put(Type_ordinal, "point-number", Next_type_ordinal++); get_or_insert(Type, point_number); // initialize get(Type, point_number).kind = CONTAINER; get(Type, point_number).name = "point-number"; get(Type, point_number).elements.push_back(reagent("xy:point")); get(Type, point_number).elements.push_back(reagent("z:number")); :(scenario copy_handles_nested_container_elements) def main [ 12:num <- copy 34 13:num <- copy 35 14:num <- copy 36 15:point-number <- copy 12:point-number/unsafe ] +mem: storing 36 in location 17 //: products of recipes can include containers :(scenario return_container) def main [ 3:point <- f 2 ] def f [ 12:num <- next-ingredient 13:num <- copy 35 return 12:point/raw ] +run: result 0 is [2, 35] +mem: storing 2 in location 3 +mem: storing 35 in location 4 //: Containers can be checked for equality with a single instruction just like //: numbers, no matter how large they are. :(scenario compare_multiple_locations) def main [ 1:num <- copy 34 # first 2:num <- copy 35 3:num <- copy 36 4:num <- copy 34 # second 5:num <- copy 35 6:num <- copy 36 7:bool <- equal 1:point-number/raw, 4:point-number/unsafe ] +mem: storing 1 in location 7 :(scenario compare_multiple_locations_2) def main [ 1:num <- copy 34 # first 2:num <- copy 35 3:num <- copy 36 4:num <- copy 34 # second 5:num <- copy 35 6:num <- copy 37 # different 7:bool <- equal 1:point-number/raw, 4:point-number/unsafe ] +mem: storing 0 in location 7 :(before "End size_of(type) Special-cases") if (type->value == -1) return 1; // error value, but we'll raise it elsewhere if (type->value == 0) return 1; if (!contains_key(Type, type->value)) { raise << "no such type " << type->value << '\n' << end(); return 0; } type_info t = get(Type, type->value); if (t.kind == CONTAINER) { // size of a container is the sum of the sizes of its elements int result = 0; for (int i = 0; i < SIZE(t.elements); ++i) { // todo: strengthen assertion to disallow mutual type recursion if (t.elements.at(i).type->value == type->value) { raise << "container " << t.name << " can't include itself as a member\n" << end(); return 0; } result += size_of(element_type(type, i)); } return result; } :(scenario stash_container) def main [ 1:num <- copy 34 # first 2:num <- copy 35 3:num <- copy 36 stash [foo:], 1:point-number/raw ] +app: foo: 34 35 36 //:: To access elements of a container, use 'get' //: 'get' takes a 'base' container and an 'offset' into it and returns the //: appropriate element of the container value. :(scenario get) def main [ 12:num <- copy 34 13:num <- copy 35 15:num <- get 12:point/raw, 1:offset # unsafe ] +mem: storing 35 in location 15 :(before "End Primitive Recipe Declarations") GET, :(before "End Primitive Recipe Numbers") put(Recipe_ordinal, "get", GET); :(before "End Primitive Recipe Checks") case GET: { if (SIZE(inst.ingredients) != 2) { raise << maybe(get(Recipe, r).name) << "'get' expects exactly 2 ingredients in '" << to_original_string(inst) << "'\n" << end(); break; } reagent/*copy*/ base = inst.ingredients.at(0); // new copy for every invocation // Update GET base in Check if (!base.type) { raise << maybe(get(Recipe, r).name) << "first ingredient of 'get' should be a container, but got '" << inst.ingredients.at(0).original_string << "'\n" << end(); break; } const type_tree* base_type = base.type; // Update GET base_type in Check if (!base_type->atom || base_type->value == 0 || !contains_key(Type, base_type->value) || get(Type, base_type->value).kind != CONTAINER) { raise << maybe(get(Recipe, r).name) << "first ingredient of 'get' should be a container, but got '" << inst.ingredients.at(0).original_string << "'\n" << end(); break; } const reagent& offset = inst.ingredients.at(1); if (!i
#!/bin/sh
# Hacky little helper called from edit/ and sandbox/ apps to save a snapshot
# of lesson/ using git.
set -e

test -d lesson/.git || exit 0  # give up if it's not a git repo

cd lesson
# explicitly say '--all' for git 1.9
git add --all .
# bug in git: git diff -q messes up --exit-code
git diff HEAD --exit-code >/dev/null || git commit -a -m . >/dev/null
inst.ingredients.at(0).name) { raise << maybe(get(Recipe, r).name) << "product of 'put' must be first ingredient '" << inst.ingredients.at(0).original_string << "', but got '" << inst.products.at(0).original_string << "'\n" << end(); break; } // End PUT Product Checks break; } :(before "End Primitive Recipe Implementations") case PUT: { reagent/*copy*/ base = current_instruction().ingredients.at(0); // Update PUT base in Run int base_address = base.value; if (base_address == 0) { raise << maybe(current_recipe_name()) << "tried to access location 0 in '" << to_original_string(current_instruction()) << "'\n" << end(); break; } const type_tree* base_type = base.type; // Update PUT base_type in Run int offset = ingredients.at(1).at(0); if (offset < 0 || offset >= SIZE(get(Type, base_type->value).elements)) break; // copied from Check above int address = base_address; for (int i = 0; i < offset; ++i) address += size_of(element_type(base.type, i)); trace(9998, "run") << "address to copy to is " << address << end(); // optimization: directly write the element rather than updating 'product' // and writing the entire container // Write Memory in PUT in Run write_products = false; for (int i = 0; i < SIZE(ingredients.at(2)); ++i) { trace("mem") << "storing " << no_scientific(ingredients.at(2).at(i)) << " in location " << address+i << end(); put(Memory, address+i, ingredients.at(2).at(i)); } break; } :(scenario put_product_error) % Hide_errors = true; def main [ local-scope load-ingredients 1:point <- merge 34, 35 3:point <- put 1:point, x:offset, 36 ] +error: main: product of 'put' must be first ingredient '1:point', but got '3:point' //:: Allow containers to be defined in Mu code. :(scenarios load) :(scenario container) container foo [ x:num y:num ] +parse: --- defining container foo +parse: element: {x: "number"} +parse: element: {y: "number"} :(scenario container_use_before_definition) container foo [ x:num y:bar ] container bar [ x:num y:num ] +parse: --- defining container foo +parse: type number: 1000 +parse: element: {x: "number"} # todo: brittle # type bar is unknown at this point, but we assign it a number +parse: element: {y: "bar"} # later type bar geon +parse: --- defining container bar +parse: type number: 1001 +parse: element: {x: "number"} +parse: element: {y: "number"} //: if a container is defined again, the new fields add to the original definition :(scenarios run) :(scenario container_extend) container foo [ x:num ] # add to previous definition container foo [ y:num ] def main [ 1:num <- copy 34 2:num <- copy 35 3:num <- get 1:foo, 0:offset 4:num <- get 1:foo, 1:offset ] +mem: storing 34 in location 3 +mem: storing 35 in location 4 :(before "End Command Handlers") else if (command == "container") { insert_container(command, CONTAINER, in); } //: Even though we allow containers to be extended, we don't allow this after //: a call to transform_all. But we do want to detect this situation and raise //: an error. This field will help us raise such errors. :(before "End type_info Fields") int Num_calls_to_transform_all_at_first_definition; :(before "End type_info Constructor") Num_calls_to_transform_all_at_first_definition = -1; :(code) void insert_container(const string& command, kind_of_type kind, istream& in) { skip_whitespace_but_not_newline(in); string name = next_word(in); if (name.empty()) { assert(!has_data(in)); raise << "incomplete container definition at end of file (0)\n" << end(); return; } // End container Name Refinements trace(9991, "parse") << "--- defining " << command << ' ' << name << end(); if (!contains_key(Type_ordinal, name) || get(Type_ordinal, name) == 0) { put(Type_ordinal, name, Next_type_ordinal++); } trace("parse") << "type number: " << get(Type_ordinal, name) << end(); skip_bracket(in, "'"+command+"' must begin with '['"); type_info& info = get_or_insert(Type, get(Type_ordinal, name)); if (info.Num_calls_to_transform_all_at_first_definition == -1) { // initial definition of this container info.Num_calls_to_transform_all_at_first_definition = Num_calls_to_transform_all; } else if (info.Num_calls_to_transform_all_at_first_definition != Num_calls_to_transform_all) { // extension after transform_all raise << "there was a call to transform_all() between the definition of container '" << name << "' and a subsequent extension. This is not supported, since any recipes that used '" << name << "' values have already been transformed and \"frozen\".\n" << end(); return; } info.name = name; info.kind = kind; while (has_data(in)) { skip_whitespace_and_comments(in); string element = next_word(in); if (element.empty()) { assert(!has_data(in)); raise << "incomplete container definition at end of file (1)\n" << end(); return; } if (element == "]") break; if (in.peek() != '\n') { raise << command << " '" << name << "' contains multiple elements on a single line. Containers and exclusive containers must only contain elements, one to a line, no code.\n" << end(); // skip rest of container declaration while (has_data(in)) { skip_whitespace_and_comments(in); if (next_word(in) == "]") break; } break; } info.elements.push_back(reagent(element)); expand_type_abbreviations(info.elements.back().type); // todo: use abbreviation before declaration replace_unknown_types_with_unique_ordinals(info.elements.back().type, info); trace(9993, "parse") << " element: " << to_string(info.elements.back()) << end(); // End Load Container Element Definition } } void replace_unknown_types_with_unique_ordinals(type_tree* type, const type_info& info) { if (!type) return; if (!type->atom) { replace_unknown_types_with_unique_ordinals(type->left, info); replace_unknown_types_with_unique_ordinals(type->right, info); return; } assert(!type->name.empty()); if (contains_key(Type_ordinal, type->name)) { type->value = get(Type_ordinal, type->name); } // End insert_container Special-cases else if (type->name != "->") { // used in recipe types put(Type_ordinal, type->name, Next_type_ordinal++); type->value = get(Type_ordinal, type->name); } } void skip_bracket(istream& in, string message) { skip_whitespace_and_comments(in); if (in.get() != '[') raise << message << '\n' << end(); } :(scenario multi_word_line_in_container_declaration) % Hide_errors = true; container foo [ x:num y:num ] +error: container 'foo' contains multiple elements on a single line. Containers and exclusive containers must only contain elements, one to a line, no code. //: support type abbreviations in container definitions :(scenario type_abbreviations_in_containers) type foo = number container bar [ x:foo ] def main [ 1:num <- copy 34 2:foo <- get 1:bar/unsafe, 0:offset ] +mem: storing 34 in location 2 :(after "Transform.push_back(expand_type_abbreviations)") Transform.push_back(expand_type_abbreviations_in_containers); // idempotent :(code) // extremely inefficient; we process all types over and over again, once for every single recipe // but it doesn't seem to cause any noticeable slowdown void expand_type_abbreviations_in_containers(vestigial const recipe_ordinal r) { for (map::iterator p = Type.begin(); p != Type.end(); ++p) { for (int i = 0; i < SIZE(p->second.elements); ++i) expand_type_abbreviations(p->second.elements.at(i).type); } } //: ensure scenarios are consistent by always starting new container //: declarations at the same type number :(before "End Reset") //: for tests Next_type_ordinal = 1000; :(before "End Test Run Initialization") assert(Next_type_ordinal < 1000); :(code) void test_error_on_transform_all_between_container_definition_and_extension() { // define a container run("container foo [\n" " a:num\n" "]\n"); // try to extend the container after transform transform_all(); CHECK_TRACE_DOESNT_CONTAIN_ERRORS(); Hide_errors = true; run("container foo [\n" " b:num\n" "]\n"); CHECK_TRACE_CONTAINS_ERRORS(); } //:: Allow container definitions anywhere in the codebase, but complain if you //:: can't find a definition at the end. :(scenario run_complains_on_unknown_types) % Hide_errors = true; def main [ # integer is not a type 1:integer <- copy 0 ] +error: main: unknown type integer in '1:integer <- copy 0' :(scenario run_allows_type_definition_after_use) def main [ 1:bar <- copy 0/unsafe ] container bar [ x:num ] $error: 0 :(before "End Type Modifying Transforms") Transform.push_back(check_or_set_invalid_types); // idempotent :(code) void check_or_set_invalid_types(const recipe_ordinal r) { recipe& caller = get(Recipe, r); trace(9991, "transform") << "--- check for invalid types in recipe " << caller.name << end(); for (int index = 0; index < SIZE(caller.steps); ++index) { instruction& inst = caller.steps.at(index); for (int i = 0; i < SIZE(inst.ingredients); ++i) check_or_set_invalid_types(inst.ingredients.at(i), caller, inst); for (int i = 0; i < SIZE(inst.products); ++i) check_or_set_invalid_types(inst.products.at(i), caller, inst); } // End check_or_set_invalid_types } void check_or_set_invalid_types(reagent& r, const recipe& caller, const instruction& inst) { // Begin check_or_set_invalid_types(r) check_or_set_invalid_types(r.type, maybe(caller.name), "'"+to_original_string(inst)+"'"); } void check_or_set_invalid_types(type_tree* type, const string& location_for_error_messages, const string& name_for_error_messages) { if (!type) return; // End Container Type Checks if (!type->atom) { check_or_set_invalid_types(type->left, location_for_error_messages, name_for_error_messages); check_or_set_invalid_types(type->right, location_for_error_messages, name_for_error_messages); return; } if (type->value == 0) return; if (!contains_key(Type, type->value)) { assert(!type->name.empty()); if (contains_key(Type_ordinal, type->name)) type->value = get(Type_ordinal, type->name); else raise << location_for_error_messages << "unknown type " << type->name << " in " << name_for_error_messages << '\n' << end(); } } :(scenario container_unknown_field) % Hide_errors = true; container foo [ x:num y:bar ] +error: foo: unknown type in y :(scenario read_container_with_bracket_in_comment) container foo [ x:num # ']' in comment y:num ] +parse: --- defining container foo +parse: element: {x: "number"} +parse: element: {y: "number"} :(scenario container_with_compound_field_type) container foo [ {x: (address array (address array character))} ] $error: 0 :(before "End transform_all") check_container_field_types(); :(code) void check_container_field_types() { for (map::iterator p = Type.begin(); p != Type.end(); ++p) { const type_info& info = p->second; // Check Container Field Types(info) for (int i = 0; i < SIZE(info.elements); ++i) check_invalid_types(info.elements.at(i).type, maybe(info.name), info.elements.at(i).name); } } void check_invalid_types(const type_tree* type, const string& location_for_error_messages, const string& name_for_error_messages) { if (!type) return; // will throw a more precise error elsewhere if (!type->atom) { check_invalid_types(type->left, location_for_error_messages, name_for_error_messages); check_invalid_types(type->right, location_for_error_messages, name_for_error_messages); return; } if (type->value != 0) { // value 0 = compound types (layer parse_tree) or type ingredients (layer shape_shifting_container) if (!contains_key(Type, type->value)) raise << location_for_error_messages << "unknown type in " << name_for_error_messages << '\n' << end(); } } string to_original_string(const type_ordinal t) { ostringstream out; if (!contains_key(Type, t)) return out.str(); const type_info& info = get(Type, t); if (info.kind == PRIMITIVE) return out.str(); out << (info.kind == CONTAINER ? "container" : "exclusive-container") << " " << info.name << " [\n"; for (int i = 0; i < SIZE(info.elements); ++i) { out << " " << info.elements.at(i).original_string << "\n"; } out << "]\n"; return out.str(); }