dwm.1


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.TH DWM 1 dwm-VERSION
.SH NAME
dwm \- dynamic window manager
.SH SYNOPSIS
.B dwm
.RB [ \-v ]
.SH DESCRIPTION
.B dwm
is a dynamic window manager for X11. It manages windows in tiling and floating
modes. Either mode can be applied dynamically, optimizing the environment for
the application in use and the task performed.
.P
In tiling mode windows are managed in a master and stacking column. The master
column contains the window which currently needs most attention, whereas the
stacking column contains all other windows. In floating mode windows can be
resized and moved freely. Dialog windows are always managed floating,
regardless of the mode selected.
.P
Windows are grouped by tags. Each window can be tagged with one or multiple
tags. Selecting a certain tag for viewing will display all windows with that
tag.
.P
.B dwm
has a small status bar which displays the text read from standard
input, if written. Besides that, it displays all available tags, and the title
of the focused window. It draws a 1-pixel border around windows to
indicate the focus state. Unfocused windows contain a small bar in front of
them displaying their tags and title.
.SH OPTIONS
.TP
.B \-v
prints version information to standard output, then exits.
.SH USAGE
.SS Status bar
.TP
.B Standard input
is read and displayed in the status text area.
.TP
.B Button1
click on a tag label views all windows with that
.BR tag .
.TP
.B Button3
click on a tag label adds/removes all windows with that
.B tag
to/from the view.
.SS Keyboard commands
.TP
.B Mod1-Return
Zoom current
.B window
to the 
.B master
column.
.TP
.B Mod1-j
Focus next
.BR window .
.TP
.B Mod1-k
Focus previous
.BR window .
.TP
.B Mod1-m
Maximize current
.BR window .
.TP
.B Mod1-[0..n]
View all windows with
.BR "tag n" .
.TP
.B Mod1-space
Toggle between
.B tiled
and
.B floating
mode (affects
.BR "all windows" ).
.TP
.B Mod1-Shift-[0..n]
Apply
.B nth tag
to current
.BR window .
.TP
.B Mod1-Shift-c
Close focused
.B window.
.TP
.B Mod1-Shift-q
Quit
.B dwm.
.TP
.B Mod1-Shift-Return
Start
.BR terminal .
.TP
.B Mod1-Control-[0..n]
Add/remove all windows with
.B tag n
to/from the view.
.TP
.B Mod1-Control-Shift-[0..n]
Add/remove
.B nth tag
to/from current
.BR window .
.SS Mouse commands
.TP
.B Mod1-Button1
Move current
.B window
while dragging.
.TP
.B Mod1-Button2
Zoom current
.B window
to the 
.B master
column.
.TP
.B Mod1-Button3
Resize current
.B window
while dragging.
.SH CUSTOMIZATION
.B dwm
is customized by creating a custom config.h and (re)compiling the source
code. This keeps it fast, secure and simple.
.SH CAVEATS
The status bar displays
.B broken pipe
when
.B dwm
has been started by
.BR xdm (1),
because it closes standard output before executing
.BR dwm .
.SH SEE ALSO
.BR dmenu (1)
//:: Container definitions can contain 'type ingredients'

//: pre-requisite: extend our notion of containers to not necessarily be
//: atomic types
:(after "Update GET base_type in Check")
base_type = get_base_type(base_type);
:(after "Update GET base_type in Run")
base_type = get_base_type(base_type);
:(after "Update PUT base_type in Check")
base_type = get_base_type(base_type);
:(after "Update PUT base_type in Run")
base_type = get_base_type(base_type);
:(after "Update MAYBE_CONVERT base_type in Check")
base_type = get_base_type(base_type);
:(after "Update base_type in element_type")
base_type = get_base_type(base_type);
:(after "Update base_type in skip_addresses")
base_type = get_base_type(base_type);
:(replace{} "const type_tree* get_base_type(const type_tree* t)")
const type_tree* get_base_type(const type_tree* t) {
  const type_tree* result = t->atom ? t : t->left;
  if (!result->atom)
    raise << "invalid type " << to_string(t) << '\n' << end();
  return result;
}

:(code)
void test_ill_formed_container() {
  Hide_errors = true;
  run(
      "def main [\n"
      "  {1: ((foo) num)} <- copy 0\n"
      "]\n"
  );
  // no crash
}

//: update size_of to handle non-atom container types

void test_size_of_shape_shifting_container() {
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:num <- merge 12, 13\n"
      "  3:foo:point <- merge 14, 15, 16\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 12 in location 1\n"
      "mem: storing 13 in location 2\n"
      "mem: storing 14 in location 3\n"
      "mem: storing 15 in location 4\n"
      "mem: storing 16 in location 5\n"
  );
}
void test_size_of_shape_shifting_container_2() {
  run(
      // multiple type ingredients
      "container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n"
      "def main [\n"
      "  1:foo:num:bool <- merge 34, true\n"
      "]\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}
void test_size_of_shape_shifting_container_3() {
  run(
      "container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n"
      "def main [\n"
      "  1:text <- new [abc]\n"
         // compound types for type ingredients
      "  {3: (foo number (address array character))} <- merge 34/x, 1:text/y\n"
      "]\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_size_of_shape_shifting_container_4() {
  run(
      "container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n"
      "container bar:_a:_b [\n"
         // dilated element
      "  {data: (foo _a (address _b))}\n"
      "]\n"
      "def main [\n"
      "  1:text <- new [abc]\n"
      "  3:bar:num:@:char <- merge 34/x, 1:text/y\n"
      "]\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_shape_shifting_container_extend() {
  run(
      "container foo:_a [\n"
      "  x:_a\n"
      "]\n"
      "container foo:_a [\n"
      "  y:_a\n"
      "]\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_shape_shifting_container_extend_error() {
  Hide_errors = true;
  run(
      "container foo:_a [\n"
      "  x:_a\n"
      "]\n"
      "container foo:_b [\n"
      "  y:_b\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "error: headers of container 'foo' must use identical type ingredients\n"
  );
}

void test_type_ingredient_must_start_with_underscore() {
  Hide_errors = true;
  run(
      "container foo:t [\n"
      "  x:num\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "error: foo: type ingredient 't' must begin with an underscore\n"
  );
}

:(before "End Globals")
// We'll use large type ordinals to mean "the following type of the variable".
// For example, if we have a generic type called foo:_elem, the type
// ingredient _elem in foo's type_info will have value START_TYPE_INGREDIENTS,
// and we'll handle it by looking in the current reagent for the next type
// that appears after foo.
extern const int START_TYPE_INGREDIENTS = 2000;
:(before "End Commandline Parsing")  // after loading .mu files
assert(Next_type_ordinal < START_TYPE_INGREDIENTS);

:(before "End type_info Fields")
map<string, type_ordinal> type_ingredient_names;

//: Suppress unknown type checks in shape-shifting containers.

:(before "Check Container Field Types(info)")
if (!info.type_ingredient_names.empty()) continue;

:(before "End container Name Refinements")
if (name.find(':') != string::npos) {
  trace(101, "parse") << "container has type ingredients; parsing" << end();
  if (!read_type_ingredients(name, command)) {
    // error; skip rest of the container definition and continue
    slurp_balanced_bracket(in);
    return;
  }
}

:(code)
bool read_type_ingredients(string& name, const string& command) {
  string save_name = name;
  istringstream in(save_name);
  name = slurp_until(in, ':');
  map<string, type_ordinal> type_ingredient_names;
  if (!slurp_type_ingredients(in, type_ingredient_names, name)) {
    return false;
  }
  if (contains_key(Type_ordinal, name)
      && contains_key(Type, get(Type_ordinal, name))) {
    const type_info& previous_info = get(Type, get(Type_ordinal, name));
    // we've already seen this container; make sure type ingredients match
    if (!type_ingredients_match(type_ingredient_names, previous_info.type_ingredient_names)) {
      raise << "headers of " << command << " '" << name << "' must use identical type ingredients\n" << end();
      return false;
    }
    return true;
  }
  // we haven't seen this container before
  if (!contains_key(Type_ordinal, name) || get(Type_ordinal, name) == 0)
    put(Type_ordinal, name, Next_type_ordinal++);
  type_info& info = get_or_insert(Type, get(Type_ordinal, name));
  info.type_ingredient_names.swap(type_ingredient_names);
  return true;
}

bool slurp_type_ingredients(istream& in, map<string, type_ordinal>& out, const string& container_name) {
  int next_type_ordinal = START_TYPE_INGREDIENTS;
  while (has_data(in)) {
    string curr = slurp_until(in, ':');
    if (curr.empty()) {
      raise << container_name << ": empty type ingredients not permitted\n" << end();
      return false;
    }
    if (!starts_with(curr, "_")) {
      raise << container_name << ": type ingredient '" << curr << "' must begin with an underscore\n" << end();
      return false;
    }
    if (out.find(curr) != out.end()) {
      raise << container_name << ": can't repeat type ingredient name'" << curr << "' in a single container definition\n" << end();
      return false;
    }
    put(out, curr, next_type_ordinal++);
  }
  return true;
}

bool type_ingredients_match(const map<string, type_ordinal>& a, const map<string, type_ordinal>& b) {
  if (SIZE(a) != SIZE(b)) return false;
  for (map<string, type_ordinal>::const_iterator p = a.begin();  p != a.end();  ++p) {
    if (!contains_key(b, p->first)) return false;
    if (p->second != get(b, p->first)) return false;
  }
  return true;
}

:(before "End insert_container Special-cases")
// check for use of type ingredients
else if (is_type_ingredient_name(type->name)) {
  type->value = get(info.type_ingredient_names, type->name);
}
:(code)
bool is_type_ingredient_name(const string& type) {
  return starts_with(type, "_");
}

:(before "End Container Type Checks")
if (type->value >= START_TYPE_INGREDIENTS
    && (type->value - START_TYPE_INGREDIENTS) < SIZE(get(Type, type->value).type_ingredient_names))
  return;

:(code)
void test_size_of_shape_shifting_exclusive_container() {
  run(
      "exclusive-container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:num <- merge 0/x, 34\n"
      "  3:foo:point <- merge 0/x, 15, 16\n"
      "  6:foo:point <- merge 1/y, 23\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "run: {1: (\"foo\" \"number\")} <- merge {0: \"literal\", \"x\": ()}, {34: \"literal\"}\n"
      "mem: storing 0 in location 1\n"
      "mem: storing 34 in location 2\n"
      "run: {3: (\"foo\" \"point\")} <- merge {0: \"literal\", \"x\": ()}, {15: \"literal\"}, {16: \"literal\"}\n"
      "mem: storing 0 in location 3\n"
      "mem: storing 15 in location 4\n"
      "mem: storing 16 in location 5\n"
      "run: {6: (\"foo\" \"point\")} <- merge {1: \"literal\", \"y\": ()}, {23: \"literal\"}\n"
      "mem: storing 1 in location 6\n"
      "mem: storing 23 in location 7\n"
      "run: return\n"
  );
  // no other stores
  CHECK_EQ(trace_count_prefix("mem", "storing"), 7);
}

:(before "End variant_type Special-cases")
if (contains_type_ingredient(element))
  replace_type_ingredients(element.type, type->right, info, " while computing variant type of exclusive-container");

:(code)
void test_get_on_shape_shifting_container() {
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:point <- merge 14, 15, 16\n"
      "  4:num <- get 1:foo:point, y:offset\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 16 in location 4\n"
  );
}

void test_get_on_shape_shifting_container_2() {
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:point <- merge 14, 15, 16\n"
      "  4:point <- get 1:foo:point, x:offset\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 14 in location 4\n"
      "mem: storing 15 in location 5\n"
  );
}

void test_get_on_shape_shifting_container_3() {
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:num/alloc-id, 2:num <- copy 0, 34\n"
      "  3:foo:&:point <- merge 1:&:point, 48\n"
      "  6:&:point <- get 1:foo:&:point, x:offset\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 0 in location 6\n"
      "mem: storing 34 in location 7\n"
  );
}

void test_get_on_shape_shifting_container_inside_container() {
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "container bar [\n"
      "  x:foo:point\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:bar <- merge 14, 15, 16, 17\n"
      "  5:num <- get 1:bar, 1:offset\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 17 in location 5\n"
  );
}

void test_get_on_complex_shape_shifting_container() {
  run(
      "container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n"
      "def main [\n"
      "  1:text <- new [abc]\n"
      "  {3: (foo number (address array character))} <- merge 34/x, 1:text/y\n"
      "  6:text <- get {3: (foo number (address array character))}, y:offset\n"
      "  8:bool <- equal 1:text, 6:text\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 1 in location 8\n"
  );
}

:(before "End element_type Special-cases")
replace_type_ingredients(element, type, info, " while computing element type of container");

:(before "End size_of(type) Non-atom Special-cases")
assert(type->left->atom);
if (!contains_key(Type, type->left->value)) {
  raise << "no such type " << type->left->value << '\n' << end();
  return 0;
}
type_info t = get(Type, type->left->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 (get_base_type(t.elements.at(i).type)->value == get_base_type(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;
}
if (t.kind == EXCLUSIVE_CONTAINER) {
  // size of an exclusive container is the size of its largest variant
  // (So like containers, it can't contain arrays.)
  int result = 0;
  for (int i = 0; i < SIZE(t.elements); ++i) {
    reagent tmp;
    tmp.type = new type_tree(*type);
    int size = size_of(variant_type(tmp, i));
    if (size > result) result = size;
  }
  // ...+1 for its tag.
  return result+1;
}

:(code)
void test_complex_shape_shifting_exclusive_container() {
  run(
      "exclusive-container foo:_a [\n"
      "  x:_a\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:text <- new [abc]\n"
      "  3:foo:point <- merge 0/variant, 34/xx, 35/xy\n"
      "  10:point, 20:bool <- maybe-convert 3:foo:point, 0/variant\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 1 in location 20\n"
      "mem: storing 35 in location 11\n"
  );
}

bool contains_type_ingredient(const reagent& x) {
  return contains_type_ingredient(x.type);
}

bool contains_type_ingredient(const type_tree* type) {
  if (!type) return false;
  if (type->atom) return type->value >= START_TYPE_INGREDIENTS;
  return contains_type_ingredient(type->left) || contains_type_ingredient(type->right);
}

void replace_type_ingredients(reagent& element, const type_tree* caller_type, const type_info& info, const string& location_for_error_messages) {
  if (contains_type_ingredient(element)) {
    if (!caller_type->right)
      raise << "illegal type " << names_to_string(caller_type) << " seems to be missing a type ingredient or three" << location_for_error_messages << '\n' << end();
    replace_type_ingredients(element.type, caller_type->right, info, location_for_error_messages);
  }
}

// replace all type_ingredients in element_type with corresponding elements of callsite_type
void replace_type_ingredients(type_tree* element_type, const type_tree* callsite_type, const type_info& container_info, const string& location_for_error_messages) {
  if (!callsite_type) return;  // error but it's already been raised above
  if (!element_type) return;
  if (!element_type->atom) {
    if (element_type->right == NULL && is_type_ingredient(element_type->left)) {
      int type_ingredient_index = to_type_ingredient_index(element_type->left);
      if (corresponding(callsite_type, type_ingredient_index, is_final_type_ingredient(type_ingredient_index, container_info))->right) {
        // replacing type ingredient at end of list, and replacement is a non-degenerate compound type -- (a b) but not (a)
        replace_type_ingredient_at(type_ingredient_index, element_type, callsite_type, container_info, location_for_error_messages);
        return;
      }
    }
    replace_type_ingredients(element_type->left, callsite_type, container_info, location_for_error_messages);
    replace_type_ingredients(element_type->right, callsite_type, container_info, location_for_error_messages);
    return;
  }
  if (is_type_ingredient(element_type))
    replace_type_ingredient_at(to_type_ingredient_index(element_type), element_type, callsite_type, container_info, location_for_error_messages);
}

const type_tree* corresponding(const type_tree* type, int index, bool final) {
  for (const type_tree* curr = type;  curr;  curr = curr->right, --index) {
    assert_for_now(!curr->atom);
    if (index == 0)
      return final ? curr : curr->left;
  }
  assert_for_now(false);
}

bool is_type_ingredient(const type_tree* type) {
  return type->atom && type->value >= START_TYPE_INGREDIENTS;
}

int to_type_ingredient_index(const type_tree* type) {
  assert(type->atom);
  return type->value-START_TYPE_INGREDIENTS;
}

void replace_type_ingredient_at(const int type_ingredient_index, type_tree* element_type, const type_tree* callsite_type, const type_info& container_info, const string& location_for_error_messages) {
  if (!has_nth_type(callsite_type, type_ingredient_index)) {
    raise << "illegal type " << names_to_string(callsite_type) << " seems to be missing a type ingredient or three" << location_for_error_messages << '\n' << end();
    return;
  }
  *element_type = *nth_type_ingredient(callsite_type, type_ingredient_index, container_info);
}

const type_tree* nth_type_ingredient(const type_tree* callsite_type, int type_ingredient_index, const type_info& container_info) {
  bool final = is_final_type_ingredient(type_ingredient_index, container_info);
  const type_tree* curr = callsite_type;
  for (int i = 0;  i < type_ingredient_index;  ++i) {
    assert(curr);
    assert(!curr->atom);
//?     cerr << "type ingredient " << i << " is " << to_string(curr->left) << '\n';
    curr = curr->right;
  }
  assert(curr);
  if (curr->atom) return curr;
  if (!final) return curr->left;
  if (!curr->right) return curr->left;
  return curr;
}

bool is_final_type_ingredient(int type_ingredient_index, const type_info& container_info) {
  for (map<string, type_ordinal>::const_iterator p = container_info.type_ingredient_names.begin();
       p != container_info.type_ingredient_names.end();
       ++p) {
    if (p->second > START_TYPE_INGREDIENTS+type_ingredient_index) return false;
  }
  return true;
}

:(before "End Unit Tests")
void test_replace_type_ingredients_entire() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "  y:num\n"
      "]\n");
  reagent callsite("x:foo:point");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: \"point\"}");
}

void test_replace_type_ingredients_tail() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem\n"
      "]\n");
  reagent callsite("x:bar:point");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"point\")}");
}

void test_replace_type_ingredients_head_tail_multiple() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem\n"
      "]\n");
  reagent callsite("x:bar:address:array:character");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"address\" \"array\" \"character\")}");
}

void test_replace_type_ingredients_head_middle() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem:num\n"
      "]\n");
  reagent callsite("x:bar:address");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"address\" \"number\")}");
}

void test_replace_last_type_ingredient_with_multiple() {
  run("container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n");
  reagent callsite("{f: (foo number (address array character))}");
  reagent element1 = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element1), "{x: \"number\"}");
  reagent element2 = element_type(callsite.type, 1);
  CHECK_EQ(to_string(element2), "{y: (\"address\" \"array\" \"character\")}");
}

void test_replace_last_type_ingredient_inside_compound() {
  run("container foo:_a:_b [\n"
      "  {x: (bar _a (address _b))}\n"
      "]\n");
  reagent callsite("f:foo:number:array:character");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(names_to_string_without_quotes(element.type), "(bar number (address array character))");
}

void test_replace_middle_type_ingredient_with_multiple() {
  run("container foo:_a:_b:_c [\n"
      "  x:_a\n"
      "  y:_b\n"
      "  z:_c\n"
      "]\n");
  reagent callsite("{f: (foo number (address array character) boolean)}");
  reagent element1 = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element1), "{x: \"number\"}");
  reagent element2 = element_type(callsite.type, 1);
  CHECK_EQ(to_string(element2), "{y: (\"address\" \"array\" \"character\")}");
  reagent element3 = element_type(callsite.type, 2);
  CHECK_EQ(to_string(element3), "{z: \"boolean\"}");
}

void test_replace_middle_type_ingredient_with_multiple2() {
  run("container foo:_key:_value [\n"
      "  key:_key\n"
      "  value:_value\n"
      "]\n");
  reagent callsite("{f: (foo (address array character) number)}");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{key: (\"address\" \"array\" \"character\")}");
}

void test_replace_middle_type_ingredient_with_multiple3() {
  run("container foo_table:_key:_value [\n"
      "  data:&:@:foo_table_row:_key:_value\n"
      "]\n"
      "\n"
      "container foo_table_row:_key:_value [\n"
      "  key:_key\n"
      "  value:_value\n"
      "]\n");
  reagent callsite("{f: (foo_table (address array character) number)}");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{data: (\"address\" \"array\" \"foo_table_row\" (\"address\" \"array\" \"character\") \"number\")}");
}

:(code)
bool has_nth_type(const type_tree* base, int n) {
  assert(n >= 0);
  if (!base) return false;
  if (n == 0) return true;
  return has_nth_type(base->right, n-1);
}

void test_get_on_shape_shifting_container_error() {
  Hide_errors = true;
  run(
      "container foo:_t [\n"
      "  x:_t\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:point <- merge 14, 15, 16\n"
      "  10:num <- get 1:foo, 1:offset\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "error: illegal type \"foo\" seems to be missing a type ingredient or three while computing element type of container\n"
  );
  // todo: improve error message
}

void test_typos_in_container_definitions() {
  Hide_errors = true;
  run(
      "container foo:_t [\n"
      "  x:adress:_t  # typo\n"
      "]\n"
      "def main [\n"
      "  local-scope\n"
      "  x:address:foo:num <- new {(foo num): type}\n"
      "]\n"
  );
  // no crash
}

void test_typos_in_recipes() {
  Hide_errors = true;
  run(
      "def foo [\n"
      "  local-scope\n"
      "  x:adress:array:number <- copy null  # typo\n"
      "]\n"
  );
  // shouldn't crash
}

//:: 'merge' on shape-shifting containers

void test_merge_check_shape_shifting_container_containing_exclusive_container() {
  run(
      "container foo:_elem [\n"
      "  x:num\n"
      "  y:_elem\n"
      "]\n"
      "exclusive-container bar [\n"
      "  x:num\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:bar <- merge 23, 1/y, 34\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 23 in location 1\n"
      "mem: storing 1 in location 2\n"
      "mem: storing 34 in location 3\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_merge_check_shape_shifting_container_containing_exclusive_container_2() {
  Hide_errors = true;
  run(
      "container foo:_elem [\n"
      "  x:num\n"
      "  y:_elem\n"
      "]\n"
      "exclusive-container bar [\n"
      "  x:num\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:bar <- merge 23, 1/y, 34, 35\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "error: main: too many ingredients in '1:foo:bar <- merge 23, 1/y, 34, 35'\n"
  );
}

void test_merge_check_shape_shifting_exclusive_container_containing_container() {
  run(
      "exclusive-container foo:_elem [\n"
      "  x:num\n"
      "  y:_elem\n"
      "]\n"
      "container bar [\n"
      "  x:num\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:bar <- merge 1/y, 23, 34\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "mem: storing 1 in location 1\n"
      "mem: storing 23 in location 2\n"
      "mem: storing 34 in location 3\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_merge_check_shape_shifting_exclusive_container_containing_container_2() {
  run(
      "exclusive-container foo:_elem [\n"
      "  x:num\n"
      "  y:_elem\n"
      "]\n"
      "container bar [\n"
      "  x:num\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:bar <- merge 0/x, 23\n"
      "]\n"
  );
  CHECK_TRACE_COUNT("error", 0);
}

void test_merge_check_shape_shifting_exclusive_container_containing_container_3() {
  Hide_errors = true;
  run(
      "exclusive-container foo:_elem [\n"
      "  x:num\n"
      "  y:_elem\n"
      "]\n"
      "container bar [\n"
      "  x:num\n"
      "  y:num\n"
      "]\n"
      "def main [\n"
      "  1:foo:bar <- merge 1/y, 23\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "error: main: too few ingredients in '1:foo:bar <- merge 1/y, 23'\n"
  );
}