# Mu - 032array.cc

      1 //: Arrays contain a variable number of elements of the same type. Their value
      2 //: starts with the length of the array.
      3 //:
      4 //: You can create arrays of containers, but containers can only contain
      5 //: elements of a fixed size, so you can't create containers containing arrays.
      6 //: Create containers containing addresses to arrays instead.
      7
      8 //: You can create arrays using 'create-array'.
      9 :(scenario create_array)
     10 def main [
     11   # create an array occupying locations 1 (for the size) and 2-4 (for the elements)
     12   1:array:num:3 <- create-array
     13 ]
     14 +run: creating array from 4 locations
     15
     16 :(before "End Primitive Recipe Declarations")
     17 CREATE_ARRAY,
     18 :(before "End Primitive Recipe Numbers")
     19 put(Recipe_ordinal, "create-array", CREATE_ARRAY);
     20 :(before "End Primitive Recipe Checks")
     21 case CREATE_ARRAY: {
     22   if (inst.products.empty()) {
     23     raise << maybe(get(Recipe, r).name) << "'create-array' needs one product and no ingredients but got '" << to_original_string(inst) << '\n' << end();
     24     break;
     25   }
     26   reagent/*copy*/ product = inst.products.at(0);
     27   // Update CREATE_ARRAY product in Check
     28   if (!is_mu_array(product)) {
     29     raise << maybe(get(Recipe, r).name) << "'create-array' cannot create non-array '" << product.original_string << "'\n" << end();
     30     break;
     31   }
     32   if (!product.type->right) {
     33     raise << maybe(get(Recipe, r).name) << "create array of what? '" << to_original_string(inst) << "'\n" << end();
     34     break;
     35   }
     36   // 'create-array' will need to check properties rather than types
     37   type_tree* array_length_from_type = product.type->right->right;
     38   if (!array_length_from_type) {
     39     raise << maybe(get(Recipe, r).name) << "create array of what size? '" << to_original_string(inst) << "'\n" << end();
     40     break;
     41   }
     42   if (!product.type->right->right->atom)
     43     array_length_from_type = array_length_from_type->left;
     44   if (!is_integer(array_length_from_type->name)) {
     45     raise << maybe(get(Recipe, r).name) << "'create-array' product should specify size of array after its element type, but got '" << product.type->right->right->name << "'\n" << end();
     46     break;
     47   }
     48   break;
     49 }
     50 :(before "End Primitive Recipe Implementations")
     51 case CREATE_ARRAY: {
     52   reagent/*copy*/ product = current_instruction().products.at(0);
     53   // Update CREATE_ARRAY product in Run
     54   int base_address = product.value;
     55   type_tree* array_length_from_type = product.type->right->right;
     56   if (!product.type->right->right->atom)
     57     array_length_from_type = array_length_from_type->left;
     58   int array_length = to_integer(array_length_from_type->name);
     59   // initialize array length, so that size_of will work
     60   trace("mem") << "storing " << array_length << " in location " << base_address << end();
     61   put(Memory, base_address, array_length);  // in array elements
     62   int size = size_of(product);  // in locations
     63   trace(9998, "run") << "creating array from " << size << " locations" << end();
     64   // initialize array
     65   for (int i = 1;  i <= size_of(product);  ++i)
     66     put(Memory, base_address+i, 0);
     67   // no need to update product
     68   write_products = false;
     69   break;
     70 }
     71
     72 :(scenario copy_array)
     73 # Arrays can be copied around with a single instruction just like numbers,
     74 # no matter how large they are.
     75 # You don't need to pass the size around, since each array variable stores its
     76 # size in memory at run-time. We'll call a variable with an explicit size a
     77 # 'static' array, and one without a 'dynamic' array since it can contain
     78 # arrays of many different sizes.
     79 def main [
     80   1:array:num:3 <- create-array
     81   2:num <- copy 14
     82   3:num <- copy 15
     83   4:num <- copy 16
     84   5:array:num <- copy 1:array:num:3
     85 ]
     86 +mem: storing 3 in location 5
     87 +mem: storing 14 in location 6
     88 +mem: storing 15 in location 7
     89 +mem: storing 16 in location 8
     90
     91 :(scenario stash_array)
     92 def main [
     93   1:array:num:3 <- create-array
     94   2:num <- copy 14
     95   3:num <- copy 15
     96   4:num <- copy 16
     97   stash [foo:], 1:array:num:3
     98 ]
     99 +app: foo: 3 14 15 16
    100
    101 :(before "End types_coercible Special-cases")
    102 if (is_mu_array(from) && is_mu_array(to))
    103   return types_strictly_match(array_element(from.type), array_element(to.type));
    104
    105 :(before "End size_of(reagent r) Special-cases")
    106 if (!r.type->atom && r.type->left->atom && r.type->left->value == Array_type_ordinal) {
    107   if (!r.type->right) {
    108     raise << maybe(current_recipe_name()) << "'" << r.original_string << "' is an array of what?\n" << end();
    109     return 1;
    110   }
    111   return /*space for length*/1 + array_length(r)*size_of(array_element(r.type));
    112 }
    113
    114 :(before "End size_of(type) Non-atom Special-cases")
    115 if (type->left->value == Array_type_ordinal) return static_array_length(type);
    116 :(code)
    117 int static_array_length(const type_tree* type) {
    118   if (!type->atom && type->right && !type->right->atom && type->right->right && !type->right->right->atom && !type->right->right->right  // exactly 3 types
    119       && type->right->right->left && type->right->right->left->atom && is_integer(type->right->right->left->name)) {  // third 'type' is a number
    120     // get size from type
    121     return to_integer(type->right->right->left->name);
    122   }
    123   cerr << to_string(type) << '\n';
    124   assert(false);
    125 }
    126
    127 //: disable the size mismatch check for arrays since the destination array
    128 //: need not be initialized
    129 :(before "End size_mismatch(x) Special-cases")
    130 if (x.type && !x.type->atom && x.type->left->value == Array_type_ordinal) return false;
    131
    132 //:: arrays inside containers
    133 //: arrays are disallowed inside containers unless their length is fixed in
    134 //: advance
    135
    136 :(scenario container_permits_static_array_element)
    137 container foo [
    138   x:array:num:3
    139 ]
    140 $error: 0
    141
    142 :(before "End insert_container Special-cases")
    143 else if (is_integer(type->name)) {  // sometimes types will contain non-type tags, like numbers for the size of an array
    144   type->value = 0;
    145 }
    146
    147 :(scenario container_disallows_dynamic_array_element)
    148 % Hide_errors = true;
    149 container foo [
    150   x:array:num
    151 ]
    152 +error: container 'foo' cannot determine size of element 'x'
    153
    154 :(before "End Load Container Element Definition")
    155 {
    156   const type_tree* type = info.elements.back().type;
    157   if (type && type->atom && type->name == "array") {
    158     raise << "container '" << name << "' doesn't specify type of array elements for '" << info.elements.back().name << "'\n" << end();
    159     continue;
    160   }
    161   if (type && !type->atom && type->left->atom && type->left->name == "array") {
    162     if (!type->right) {
    163       raise << "container '" << name << "' doesn't specify type of array elements for '" << info.elements.back().name << "'\n" << end();
    164       continue;
    165     }
    166     if (!type->right->right || !is_integer(type->right->right->left->name)) {  // array has no length
    167       raise << "container '" << name << "' cannot determine size of element '" << info.elements.back().name << "'\n" << end();
    168       continue;
    169     }
    170   }
    171 }
    172
    173 //: disable the size mismatch check for 'merge' instructions since containers
    174 //: can contain arrays, and since we already do plenty of checking for them
    175 :(before "End size_mismatch(x) Special-cases")
    176 if (current_call().running_step_index < SIZE(get(Recipe, current_call().running_recipe).steps)
    177     && current_instruction().operation == MERGE) {
    178   return false;
    179 }
    180
    181 :(scenario merge_static_array_into_container)
    182 container foo [
    183   x:num
    184   y:array:num:3
    185 ]
    186 def main [
    187   1:array:num:3 <- create-array
    188   10:foo <- merge 34, 1:array:num:3
    189 ]
    190 # no errors
    191
    192 :(scenario code_inside_container)
    193 % Hide_errors = true;
    194 container card [
    195   rank:num <- next-ingredient
    196 ]
    197 def foo [
    198   1:card <- merge 3
    199   2:num <- get 1:card rank:offset
    200 ]
    201 # shouldn't die
    202
    203 //:: To access elements of an array, use 'index'
    204
    205 :(scenario index)
    206 def main [
    207   1:array:num:3 <- create-array
    208   2:num <- copy 14
    209   3:num <- copy 15
    210   4:num <- copy 16
    211   10:num <- index 1:array:num:3, 0/index  # the index must be a non-negative whole number
    212 ]
    213 +mem: storing 14 in location 10
    214
    215 :(scenario index_compound_element)
    216 def main [
    217   {1: (array (address number) 3)} <- create-array
    218   # skip alloc id
    219   3:num <- copy 14
    220   # skip alloc id
    221   5:num <- copy 15
    222   # skip alloc id
    223   7:num <- copy 16
    224   10:address:num <- index {1: (array (address number) 3)}, 0
    225 ]
    226 # skip alloc id
    227 +mem: storing 14 in location 11
    228
    229 :(scenario index_direct_offset)
    230 def main [
    231   1:array:num:3 <- create-array
    232   2:num <- copy 14
    233   3:num <- copy 15
    234   4:num <- copy 16
    235   10:num <- copy 0
    236   20:num <- index 1:array:num, 10:num
    237 ]
    238 +mem: storing 14 in location 20
    239
    240 :(before "End Primitive Recipe Declarations")
    241 INDEX,
    242 :(before "End Primitive Recipe Numbers")
    243 put(Recipe_ordinal, "index", INDEX);
    244 :(before "End Primitive Recipe Checks")
    245 case INDEX: {
    246   if (SIZE(inst.ingredients) != 2) {
    247     raise << maybe(get(Recipe, r).name) << "'index' expects exactly 2 ingredients in '" << to_original_string(inst) << "'\n" << end();
    248     break;
    249   }
    250   reagent/*copy*/ base = inst.ingredients.at(0);
    251   // Update INDEX base in Check
    252   if (!is_mu_array(base)) {
    253     raise << maybe(get(Recipe, r).name) << "'index' on a non-array '" << base.original_string << "'\n" << end();
    254     break;
    255   }
    256   reagent/*copy*/ index = inst.ingredients.at(1);
    257   // Update INDEX index in Check
    258   if (!is_mu_number(index)) {
    259     raise << maybe(get(Recipe, r).name) << "second ingredient of 'index' should be a number, but got '" << index.original_string << "'\n" << end();
    260     break;
    261   }
    262   if (inst.products.empty()) break;
    263   reagent/*copy*/ product = inst.products.at(0);
    264   // Update INDEX product in Check
    265   reagent/*local*/ element(copy_array_element(base.type));
    266   if (!types_coercible(product, element)) {
    267     raise << maybe(get(Recipe, r).name) << "'index' on '" << base.original_string << "' can't be saved in '" << product.original_string << "'; type should be '" << names_to_string_without_quotes(element.type) << "'\n" << end();
    268     break;
    269   }
    270   break;
    271 }
    272 :(before "End Primitive Recipe Implementations")
    273 case INDEX: {
    274   reagent/*copy*/ base = current_instruction().ingredients.at(0);
    275   // Update INDEX base in Run
    276   int base_address = base.value;
    277   trace(9998, "run") << "base address is " << base_address << end();
    278   if (base_address == 0) {
    279     raise << maybe(current_recipe_name()) << "tried to access location 0 in '" << to_original_string(current_instruction()) << "'\n" << end();
    280     break;
    281   }
    282   reagent/*copy*/ index = current_instruction().ingredients.at(1);
    283   // Update INDEX index in Run
    284   vector<double> index_val(read_memory(index));
    285   if (index_val.at(0) < 0 || index_val.at(0) >= get_or_insert(Memory, base_address)) {
    286     raise << maybe(current_recipe_name()) << "invalid index " << no_scientific(index_val.at(0)) << " in '" << to_original_string(current_instruction()) << "'\n" << end();
    287     break;
    288   }
    289   reagent/*local*/ element(copy_array_element(base.type));
    290   element.set_value(base_address + /*skip length*/1 + index_val.at(0)*size_of(element.type));
    291   trace(9998, "run") << "address to copy is " << element.value << end();
    292   trace(9998, "run") << "its type is " << to_string(element.type) << end();
    293   // Read element
    294   products.push_back(read_memory(element));
    295   break;
    296 }
    297
    298 :(code)
    299 type_tree* copy_array_element(const type_tree* type) {
    300   return new type_tree(*array_element(type));
    301 }
    302
    303 type_tree* array_element(const type_tree* type) {
    304   assert(type->right);
    305   if (type->right->atom) {
    306     return type->right;
    307   }
    308   else if (!type->right->right) {
    309     return type->right->left;
    310   }
    311   // hack: support array:num:3 without requiring extra parens
    312   else if (type->right->right->left && type->right->right->left->atom && is_integer(type->right->right->left->name)) {
    313     assert(!type->right->right->right);
    314     return type->right->left;
    315   }
    316   return type->right;
    317 }
    318
    319 int array_length(const reagent& x) {
    320   // x should already be canonized.
    321   // hack: look for length in type
    322   if (!x.type->atom && x.type->right && !x.type->right->atom && x.type->right->right && !x.type->right->right->atom && !x.type->right->right->right  // exactly 3 types
    323       && x.type->right->right->left && x.type->right->right->left->atom && is_integer(x.type->right->right->left->name)) {  // third 'type' is a number
    324     // get size from type
    325     return to_integer(x.type->right->right->left->name);
    326   }
    327   // this should never happen at transform time
    328   return get_or_insert(Memory, x.value);
    329 }
    330
    331 :(before "End Unit Tests")
    332 void test_array_length_compound() {
    333   put(Memory, 1, 3);
    334   put(Memory, 2, 14);
    335   put(Memory, 3, 15);
    336   put(Memory, 4, 16);
    337   reagent x("1:array:address:num");  // 3 types, but not a static array
    338   populate_value(x);
    339   CHECK_EQ(array_length(x), 3);
    340 }
    341
    342 void test_array_length_static() {
    343   reagent x("1:array:num:3");
    344   CHECK_EQ(array_length(x), 3);
    345 }
    346
    347 :(scenario index_truncates)
    348 def main [
    349   1:array:num:3 <- create-array
    350   2:num <- copy 14
    351   3:num <- copy 15
    352   4:num <- copy 16
    353   10:num <- index 1:array:num:3, 1.5  # non-whole number
    354 ]
    355 # fraction is truncated away
    356 +mem: storing 15 in location 10
    357
    358 :(scenario index_out_of_bounds)
    359 % Hide_errors = true;
    360 def main [
    361   1:array:point:3 <- create-array
    362   index 1:array:point:3, 4  # less than size of array in locations, but larger than its length in elements
    363 ]
    364 +error: main: invalid index 4 in 'index 1:array:point:3, 4'
    365
    366 :(scenario index_out_of_bounds_2)
    367 % Hide_errors = true;
    368 def main [
    369   1:array:num:3 <- create-array
    370   index 1:array:num, -1
    371 ]
    372 +error: main: invalid index -1 in 'index 1:array:num, -1'
    373
    374 :(scenario index_product_type_mismatch)
    375 % Hide_errors = true;
    376 def main [
    377   1:array:point:3 <- create-array
    378   10:num <- index 1:array:point, 0
    379 ]
    380 +error: main: 'index' on '1:array:point' can't be saved in '10:num'; type should be 'point'
    381
    382 //: we might want to call 'index' without saving the results, say in a sandbox
    383
    384 :(scenario index_without_product)
    385 def main [
    386   1:array:num:3 <- create-array
    387   index 1:array:num:3, 0
    388 ]
    389 # just don't die
    390
    391 //:: To write to elements of arrays, use 'put'.
    392
    393 :(scenario put_index)
    394 def main [
    395   1:array:num:3 <- create-array
    396   1:array:num <- put-index 1:array:num, 1, 34
    397 ]
    398 +mem: storing 34 in location 3
    399
    400 :(before "End Primitive Recipe Declarations")
    401 PUT_INDEX,
    402 :(before "End Primitive Recipe Numbers")
    403 put(Recipe_ordinal, "put-index", PUT_INDEX);
    404 :(before "End Primitive Recipe Checks")
    405 case PUT_INDEX: {
    406   if (SIZE(inst.ingredients) != 3) {
    407     raise << maybe(get(Recipe, r).name) << "'put-index' expects exactly 3 ingredients in '" << to_original_string(inst) << "'\n" << end();
    408     break;
    409   }
    410   reagent/*copy*/ base = inst.ingredients.at(0);
    411   // Update PUT_INDEX base in Check
    412   if (!is_mu_array(base)) {
    413     raise << maybe(get(Recipe, r).name) << "'put-index' on a non-array '" << base.original_string << "'\n" << end();
    414     break;
    415   }
    416   reagent/*copy*/ index = inst.ingredients.at(1);
    417   // Update PUT_INDEX index in Check
    418   if (!is_mu_number(index)) {
    419     raise << maybe(get(Recipe, r).name) << "second ingredient of 'put-index' should have type 'number', but got '" << inst.ingredients.at(1).original_string << "'\n" << end();
    420     break;
    421   }
    422   reagent/*copy*/ value = inst.ingredients.at(2);
    423   // Update PUT_INDEX value in Check
    424   reagent/*local*/ element(copy_array_element(base.type));
    425   if (!types_coercible(element, value)) {
    426     raise << maybe(get(Recipe, r).name) << "'put-index " << base.original_string << ", " << inst.ingredients.at(1).original_string << "' should store " << names_to_string_without_quotes(element.type) << " but '" << value.name << "' has type " << names_to_string_without_quotes(value.type) << '\n' << end();
    427     break;
    428   }
    429   if (inst.products.empty()) break;  // no more checks necessary
    430   if (inst.products.at(0).name != inst.ingredients.at(0).name) {
    431     raise << maybe(get(Recipe, r).name) << "product of 'put-index' must be first ingredient '" << inst.ingredients.at(0).original_string << "', but got '" << inst.products.at(0).original_string << "'\n" << end();
    432     break;
    433   }
    434   // End PUT_INDEX Product Checks
    435   break;
    436 }
    437 :(before "End Primitive Recipe Implementations")
    438 case PUT_INDEX: {
    439   reagent/*copy*/ base = current_instruction().ingredients.at(0);
    440   // Update PUT_INDEX base in Run
    441   int base_address = base.value;
    442   if (base_address == 0) {
    443     raise << maybe(current_recipe_name()) << "tried to access location 0 in '" << to_original_string(current_instruction()) << "'\n" << end();
    444     break;
    445   }
    446   reagent/*copy*/ index = current_instruction().ingredients.at(1);
    447   // Update PUT_INDEX index in Run
    448   vector<double> index_val(read_memory(index));
    449   if (index_val.at(0) < 0 || index_val.at(0) >= get_or_insert(Memory, base_address)) {
    450     raise << maybe(current_recipe_name()) << "invalid index " << no_scientific(index_val.at(0)) << " in '" << to_original_string(current_instruction()) << "'\n" << end();
    451     break;
    452   }
    453   int address = base_address + /*skip length*/1 + index_val.at(0)*size_of(array_element(base.type));
    454   trace(9998, "run") << "address to copy to is " << address << end();
    455   // optimization: directly write the element rather than updating 'product'
    456   // and writing the entire array
    457   write_products = false;
    458   vector<double> value = read_memory(current_instruction().ingredients.at(2));
    459   // Write Memory in PUT_INDEX in Run
    460   for (int i = 0;  i < SIZE(value);  ++i) {
    461     trace("mem") << "storing " << no_scientific(value.at(i)) << " in location " << address+i << end();
    462     put(Memory, address+i, value.at(i));
    463   }
    464   break;
    465 }
    466
    467 :(scenario put_index_out_of_bounds)
    468 % Hide_errors = true;
    469 def main [
    470   1:array:point:3 <- create-array
    471   8:point <- merge 34, 35
    472   1:array:point <- put-index 1:array:point, 4, 8:point  # '4' is less than size of array in locations, but larger than its length in elements
    473 ]
    474 +error: main: invalid index 4 in '1:array:point <- put-index 1:array:point, 4, 8:point'
    475
    476 :(scenario put_index_out_of_bounds_2)
    477 % Hide_errors = true;
    478 def main [
    479   1:array:point:3 <- create-array
    480   10:point <- merge 34, 35
    481   1:array:point <- put-index 1:array:point, -1, 10:point
    482 ]
    483 +error: main: invalid index -1 in '1:array:point <- put-index 1:array:point, -1, 10:point'
    484
    485 :(scenario put_index_product_error)
    486 % Hide_errors = true;
    487 def main [
    488   1:array:num:3 <- create-array
    489   4:array:num:3 <- put-index 1:array:num:3, 0, 34
    490 ]
    491 +error: main: product of 'put-index' must be first ingredient '1:array:num:3', but got '4:array:num:3'
    492
    493 //:: compute the length of an array
    494
    495 :(scenario array_length)
    496 def main [
    497   1:array:num:3 <- create-array
    498   10:num <- length 1:array:num
    499 ]
    500 +mem: storing 3 in location 10
    501
    502 :(before "End Primitive Recipe Declarations")
    503 LENGTH,
    504 :(before "End Primitive Recipe Numbers")
    505 put(Recipe_ordinal, "length", LENGTH);
    506 :(before "End Primitive Recipe Checks")
    507 case LENGTH: {
    508   if (SIZE(inst.ingredients) != 1) {
    509     raise << maybe(get(Recipe, r).name) << "'length' expects exactly 2 ingredients in '" << to_original_string(inst) << "'\n" << end();
    510     break;
    511   }
    512   reagent/*copy*/ array = inst.ingredients.at(0);
    513   // Update LENGTH array in Check
    514   if (!is_mu_array(array)) {
    515     raise << "tried to calculate length of non-array '" << array.original_string << "'\n" << end();
    516     break;
    517   }
    518   break;
    519 }
    520 :(before "End Primitive Recipe Implementations")
    521 case LENGTH: {
    522   reagent/*copy*/ array = current_instruction().ingredients.at(0);
    523   // Update LENGTH array in Run
    524   if (array.value == 0) {
    525     raise << maybe(current_recipe_name()) << "tried to access location 0 in '" << to_original_string(current_instruction()) << "'\n" << end();
    526     break;
    527   }
    528   products.resize(1);
    529   products.at(0).push_back(get_or_insert(Memory, array.value));
    530   break;
    531 }
    532
    533 //: optimization: none of the instructions in this layer use 'ingredients' so
    534 //: stop copying potentially huge arrays into it.
    535 :(before "End should_copy_ingredients Special-cases")
    536 recipe_ordinal r = current_instruction().operation;
    537 if (r == CREATE_ARRAY || r == INDEX || r == PUT_INDEX || r == LENGTH)
    538   return false;