//: Allow code for recipes to be pulled in from multiple places and inserted //: at special labels called 'waypoints' using two new top-level commands: //: before //: after //: Most labels are local: they must be unique to a recipe, and are invisible //: outside the recipe. However, waypoints are global: a recipe can have //: multiple of them, you can't use them as jump targets. :(before "End is_jump_target Special-cases") if (is_waypoint(label)) return false; //: Waypoints are always surrounded by '<>', e.g. <handle-request>. :(code) bool is_waypoint(string label) { return *label.begin() == '<' && *label.rbegin() == '>'; } void test_tangle_before() { run( "def main [\n" " 1:num <- copy 0\n" " <label1>\n" " 3:num <- copy 0\n" "]\n" "before <label1> [\n" " 2:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 0 in location 1\n" "mem: storing 0 in location 2\n" "mem: storing 0 in location 3\n" ); // nothing else CHECK_TRACE_COUNT("mem", 3); } //: while loading recipes, load before/after fragments :(before "End Globals") map<string /*label*/, recipe> Before_fragments, After_fragments; set<string /*label*/> Fragments_used; :(before "End Reset") Before_fragments.clear(); After_fragments.clear(); Fragments_used.clear(); :(before "End Command Handlers") else if (command == "before") { string label = next_word(in); if (label.empty()) { assert(!has_data(in)); raise << "incomplete 'before' block at end of file\n" << end(); return result; } recipe tmp; slurp_body(in, tmp); if (is_waypoint(label)) Before_fragments[label].steps.insert(Before_fragments[label].steps.end(), tmp.steps.begin(), tmp.steps.end()); else raise << "can't tangle before non-waypoint " << label << '\n' << end(); // End before Command Handler } else if (command == "after") { string label = next_word(in); if (label.empty()) { assert(!has_data(in)); raise << "incomplete 'after' block at end of file\n" << end(); return result; } recipe tmp; slurp_body(in, tmp); if (is_waypoint(label)) After_fragments[label].steps.insert(After_fragments[label].steps.begin(), tmp.steps.begin(), tmp.steps.end()); else raise << "can't tangle after non-waypoint " << label << '\n' << end(); // End after Command Handler } //: after all recipes are loaded, insert fragments at appropriate labels. :(after "Begin Instruction Inserting/Deleting Transforms") Transform.push_back(insert_fragments); // NOT idempotent //: We might need to perform multiple passes, in case inserted fragments //: include more labels that need further insertions. Track which labels we've //: already processed using an extra field. :(before "End instruction Fields") mutable bool tangle_done; :(before "End instruction Constructor") tangle_done = false; :(code) void insert_fragments(const recipe_ordinal r) { insert_fragments(get(Recipe, r)); } void insert_fragments(recipe& r) { trace(101, "transform") << "--- insert fragments into recipe " << r.name << end(); bool made_progress = true; int pass = 0; while (made_progress) { made_progress = false; // create a new vector because insertions invalidate iterators vector<instruction> result; for (int i = 0; i < SIZE(r.steps); ++i) { const instruction& inst = r.steps.at(i); if (!inst.is_label || !is_waypoint(inst.label) || inst.tangle_done) { result.push_back(inst); continue; } inst.tangle_done = true; made_progress = true; Fragments_used.insert(inst.label); ostringstream prefix; prefix << '+' << r.name << '_' << pass << '_' << i; // ok to use contains_key even though Before_fragments uses [], // because appending an empty recipe is a noop if (contains_key(Before_fragments, inst.label)) { trace(102, "transform") << "insert fragments before label " << inst.label << end(); append_fragment(result, Before_fragments[inst.label].steps, prefix.str()); } result.push_back(inst); if (contains_key(After_fragments, inst.label)) { trace(102, "transform") << "insert fragments after label " << inst.label << end(); append_fragment(result, After_fragments[inst.label].steps, prefix.str()); } } r.steps.swap(result); ++pass; } } void append_fragment(vector<instruction>& base, const vector<instruction>& patch, const string prefix) { // append 'patch' to 'base' while keeping 'base' oblivious to any new jump // targets in 'patch' oblivious to 'base' by prepending 'prefix' to them. // we might tangle the same fragment at multiple points in a single recipe, // and we need to avoid duplicate jump targets. // so we'll keep jump targets local to the specific before/after fragment // that introduces them. set<string> jump_targets; for (int i = 0; i < SIZE(patch); ++i) { const instruction& inst = patch.at(i); if (inst.is_label && is_jump_target(inst.label)) jump_targets.insert(inst.label); } for (int i = 0; i < SIZE(patch); ++i) { instruction inst = patch.at(i); if (inst.is_label) { if (contains_key(jump_targets, inst.label)) inst.label = prefix+inst.label; base.push_back(inst); continue; } for (int j = 0; j < SIZE(inst.ingredients); ++j) { reagent& x = inst.ingredients.at(j); if (is_jump_target(x.name) && contains_key(jump_targets, x.name)) x.name = prefix+x.name; } base.push_back(inst); } } //: complain about unapplied fragments //: This can't run during transform because later (shape-shifting recipes) //: we'll encounter situations where fragments might get used long after //: they're loaded, and we might run transform_all in between. To avoid //: spurious errors, run this check right at the end, after all code is //: loaded, right before we run main. :(before "End Commandline Parsing") check_insert_fragments(); :(code) void check_insert_fragments() { for (map<string, recipe>::iterator p = Before_fragments.begin(); p != Before_fragments.end(); ++p) { if (!contains_key(Fragments_used, p->first)) raise << "could not locate insert before label " << p->first << '\n' << end(); } for (map<string, recipe>::iterator p = After_fragments.begin(); p != After_fragments.end(); ++p) { if (!contains_key(Fragments_used, p->first)) raise << "could not locate insert after label " << p->first << '\n' << end(); } } void test_tangle_before_and_after() { run( "def main [\n" " 1:num <- copy 0\n" " <label1>\n" " 4:num <- copy 0\n" "]\n" "before <label1> [\n" " 2:num <- copy 0\n" "]\n" "after <label1> [\n" " 3:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 0 in location 1\n" "mem: storing 0 in location 2\n" // label1 "mem: storing 0 in location 3\n" "mem: storing 0 in location 4\n" ); // nothing else CHECK_TRACE_COUNT("mem", 4); } void test_tangle_ignores_jump_target() { Hide_errors = true; run( "def main [\n" " 1:num <- copy 0\n" " +label1\n" " 4:num <- copy 0\n" "]\n" "before +label1 [\n" " 2:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "error: can't tangle before non-waypoint +label1\n" ); } void test_tangle_keeps_labels_separate() { run( "def main [\n" " 1:num <- copy 0\n" " <label1>\n" " <label2>\n" " 6:num <- copy 0\n" "]\n" "before <label1> [\n" " 2:num <- copy 0\n" "]\n" "after <label1> [\n" " 3:num <- copy 0\n" "]\n" "before <label2> [\n" " 4:num <- copy 0\n" "]\n" "after <label2> [\n" " 5:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 0 in location 1\n" "mem: storing 0 in location 2\n" // label1 "mem: storing 0 in location 3\n" // 'after' fragments for earlier label always go before 'before' // fragments for later label "mem: storing 0 in location 4\n" // label2 "mem: storing 0 in location 5\n" "mem: storing 0 in location 6\n" ); // nothing else CHECK_TRACE_COUNT("mem", 6); } void test_tangle_stacks_multiple_fragments() { run( "def main [\n" " 1:num <- copy 0\n" " <label1>\n" " 6:num <- copy 0\n" "]\n" "before <label1> [\n" " 2:num <- copy 0\n" "]\n" "after <label1> [\n" " 3:num <- copy 0\n" "]\n" "before <label1> [\n" " 4:num <- copy 0\n" "]\n" "after <label1> [\n" " 5:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 0 in location 1\n" // 'before' fragments stack in order "mem: storing 0 in location 2\n" "mem: storing 0 in location 4\n" // label1 // 'after' fragments stack in reverse order "mem: storing 0 in location 5\n" "mem: storing 0 in location 3\n" "mem: storing 0 in location 6\n" ); // nothing CHECK_TRACE_COUNT("mem", 6); } void test_tangle_supports_fragments_with_multiple_instructions() { run( "def main [\n" " 1:num <- copy 0\n" " <label1>\n" " 6:num <- copy 0\n" "]\n" "before <label1> [\n" " 2:num <- copy 0\n" " 3:num <- copy 0\n" "]\n" "after <label1> [\n" " 4:num <- copy 0\n" " 5:num <- copy 0\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 0 in location 1\n" "mem: storing 0 in location 2\n" "mem: storing 0 in location 3\n" // label1 "mem: storing 0 in location 4\n" "mem: storing 0 in location 5\n" "mem: storing 0 in location 6\n" ); // nothing else CHECK_TRACE_COUNT("mem", 6); } void test_tangle_tangles_into_all_labels_with_same_name() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " 4:num <- copy 10\n" " recipe2\n" "]\n" "def recipe2 [\n" " 1:num <- copy 11\n" " <label1>\n" " 4:num <- copy 11\n" "]\n" "before <label1> [\n" " 2:num <- copy 12\n" "]\n" "after <label1> [\n" " 3:num <- copy 12\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" "mem: storing 12 in location 2\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 10 in location 4\n" // recipe2 "mem: storing 11 in location 1\n" "mem: storing 12 in location 2\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 11 in location 4\n" ); // nothing else CHECK_TRACE_COUNT("mem", 8); } void test_tangle_tangles_into_all_labels_with_same_name_2() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " <label1>\n" " 4:num <- copy 10\n" "]\n" "before <label1> [\n" " 2:num <- copy 12\n" "]\n" "after <label1> [\n" " 3:num <- copy 12\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" "mem: storing 12 in location 2\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 12 in location 2\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 10 in location 4\n" ); // nothing else CHECK_TRACE_COUNT("mem", 6); } void test_tangle_tangles_into_all_labels_with_same_name_3() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " <foo>\n" " 4:num <- copy 10\n" "]\n" "before <label1> [\n" " 2:num <- copy 12\n" "]\n" "after <label1> [\n" " 3:num <- copy 12\n" "]\n" "after <foo> [\n" " <label1>\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" "mem: storing 12 in location 2\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 12 in location 2\n" // foo/label1 "mem: storing 12 in location 3\n" "mem: storing 10 in location 4\n" ); // nothing else CHECK_TRACE_COUNT("mem", 6); } void test_tangle_handles_jump_target_inside_fragment() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " 4:num <- copy 10\n" "]\n" "before <label1> [\n" " jump +label2:label\n" " 2:num <- copy 12\n" " +label2\n" " 3:num <- copy 12\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 10 in location 4\n" ); // ignored by jump CHECK_TRACE_DOESNT_CONTAIN("mem: storing 12 in label 2"); // nothing else CHECK_TRACE_COUNT("mem", 3); } void test_tangle_renames_jump_target() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " +label2\n" " 4:num <- copy 10\n" "]\n" "before <label1> [\n" " jump +label2:label\n" " 2:num <- copy 12\n" " +label2 # renamed\n" " 3:num <- copy 12\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" // label1 "mem: storing 12 in location 3\n" "mem: storing 10 in location 4\n" ); // ignored by jump CHECK_TRACE_DOESNT_CONTAIN("mem: storing 12 in label 2"); // nothing else CHECK_TRACE_COUNT("mem", 3); } void test_tangle_jump_to_base_recipe() { run( "def main [\n" " 1:num <- copy 10\n" " <label1>\n" " +label2\n" " 4:num <- copy 10\n" "]\n" "before <label1> [\n" " jump +label2:label\n" " 2:num <- copy 12\n" " 3:num <- copy 12\n" "]\n" ); CHECK_TRACE_CONTENTS( "mem: storing 10 in location 1\n" // label1 "mem: storing 10 in location 4\n" ); // ignored by jump CHECK_TRACE_DOESNT_CONTAIN("mem: storing 12 in label 2"); CHECK_TRACE_DOESNT_CONTAIN("mem: storing 12 in location 3"); // nothing else CHECK_TRACE_COUNT("mem", 2); } //: ensure that there are no new fragments created for a label after it's already been inserted to void test_new_fragment_after_tangle() { // define a recipe load("def foo [\n" " local-scope\n" " <label>\n" "]\n" "after <label> [\n" " 1:num/raw <- copy 34\n" "]\n"); transform_all(); CHECK_TRACE_DOESNT_CONTAIN_ERRORS(); Hide_errors = true; // try to tangle into recipe foo after transform load("before <label> [\n" " 2:num/raw <- copy 35\n" "]\n"); CHECK_TRACE_CONTAINS_ERRORS(); } :(before "End before Command Handler") if (contains_key(Fragments_used, label)) raise << "we've already tangled some code at label " << label << " in a previous call to transform_all(). Those locations won't be updated.\n" << end(); :(before "End after Command Handler") if (contains_key(Fragments_used, label)) raise << "we've already tangled some code at label " << label << " in a previous call to transform_all(). Those locations won't be updated.\n" << end();