some builtin class methods were added

- check a string contains another with `in` keyword
- Number: isint, isbyte
- String: find, replace, split, startswith, endswith, strip
- Map: clear, has, get, pop
- list: insert, clear, find, pop
- removed str_sub builtin function as its redunent since we have
  range slice over strings.
- moved lower, upper attributes of strings as methods

docs/README.md

@@ -11,7 +11,7 @@ which is less than <strong>300KB</strong> and the language itself can be compile
 </p>
 
 <div class="center">
-    <a class="button" target="_blank" href="./tryonline.html"> Try Online </a>
+    <a class="button" target="_blank" href="./try-online.html"> Try Online </a>
     <a class="button" target="_blank" href="https://www.github.com/ThakeeNathees/pocketlang/"> GitHub </a>
 </div>
 

scripts/run_tests.py

@@ -24,7 +24,6 @@ TEST_SUITE = {
     "lang/builtin_ty.pk",
     "lang/class.pk",
     "lang/closure.pk",
-    "lang/core.pk",
     "lang/controlflow.pk",
     "lang/fibers.pk",
     "lang/functions.pk",

src/core/core.c

@@ -489,34 +489,6 @@ DEF(coreExit,
   exit((int)value);
 }
 
-// String functions.
-// -----------------
-
-DEF(coreStrSub,
-  "str_sub(str:string, pos:num, len:num) -> string\n"
-  "Returns a substring from a given string supplied. In addition, "
-  "the position and length of the substring are provided when this "
-  "function is called. For example: `str_sub(str, pos, len)`.") {
-
-  String* str;
-  int64_t pos, len;
-
-  if (!validateArgString(vm, 1, &str)) return;
-  if (!validateInteger(vm, ARG(2), &pos, "Argument 2")) return;
-  if (!validateInteger(vm, ARG(3), &len, "Argument 3")) return;
-
-  if (pos < 0 || str->length < pos)
-    RET_ERR(newString(vm, "Index out of range."));
-
-  if (str->length < pos + len)
-    RET_ERR(newString(vm, "Substring length exceeded the limit."));
-
-  // Edge case, empty string.
-  if (len == 0) RET(VAR_OBJ(newStringLength(vm, "", 0)));
-
-  RET(VAR_OBJ(newStringLength(vm, str->data + pos, (uint32_t)len)));
-}
-
 // List functions.
 // ---------------
 
@@ -557,21 +529,6 @@ DEF(coreListJoin,
   RET(VAR_OBJ(str));
 }
 
-// Map functions.
-// --------------
-
-DEF(coreMapRemove,
-  "map_remove(self:map, key:var) -> var\n"
-  "Remove the [key] from the map [self] and return it's value if the key "
-  "exists, otherwise it'll return null.") {
-
-  Map* map;
-  if (!validateArgMap(vm, 1, &map)) return;
-  Var key = ARG(2);
-
-  RET(mapRemoveKey(vm, map, key));
-}
-
 static void initializeBuiltinFN(PKVM* vm, Closure** bfn, const char* name,
                                 int length, int arity, pkNativeFn ptr,
                                 const char* docstring) {
@@ -601,19 +558,10 @@ static void initializeBuiltinFunctions(PKVM* vm) {
   INITIALIZE_BUILTIN_FN("input",     coreInput,   -1);
   INITIALIZE_BUILTIN_FN("exit",      coreExit,    -1);
 
-  // FIXME:
-  // move this functions as methods. and make "append()" a builtin.
-
-  // String functions.
-  INITIALIZE_BUILTIN_FN("str_sub", coreStrSub, 3);
-
   // List functions.
   INITIALIZE_BUILTIN_FN("list_append", coreListAppend, 2);
   INITIALIZE_BUILTIN_FN("list_join",   coreListJoin,   1);
 
-  // Map functions.
-  INITIALIZE_BUILTIN_FN("map_remove", coreMapRemove, 2);
-
 #undef INITIALIZE_BUILTIN_FN
 }
 
@@ -850,9 +798,167 @@ DEF(_numberIsbyte,
   RET(VAR_BOOL((floor(n) == n) && (0x00 <= n && n <= 0xff)));
 }
 
+DEF(_stringFind,
+  "String.find(sub:String[, start:Number=0]) -> Number\n"
+  "Returns the first index of the substring [sub] found from the "
+  "[start] index") {
+
+  if (!pkCheckArgcRange(vm, ARGC, 1, 2)) return;
+
+  String* sub;
+  if (!validateArgString(vm, 1, &sub)) return;
+
+  int64_t start = 0;
+  if (ARGC == 2) {
+    if (!validateInteger(vm, ARG(2), &start, "Argument 1")) return;
+  }
+
+  String* self = (String*) AS_OBJ(SELF);
+
+  if (self->length <= start) {
+    RET(VAR_NUM((double) -1));
+  }
+
+  // FIXME: Pocketlang strings can contain \x00 ie. NULL byte and strstr
+  // doesn't support them. However pocketlang strings always ends with a null
+  // byte so the match won't go outside of the string.
+  const char* match = strstr(self->data + start, sub->data);
+
+  if (match == NULL) RET(VAR_NUM((double) -1));
+
+  ASSERT_INDEX(match - self->data, self->capacity);
+  RET(VAR_NUM((double) (match - self->data)));
+}
+
+DEF(_stringReplace,
+  "String.replace(old:Sttring, new:String[, count:Number=-1]) -> String\n"
+  "Returns a copy of the string where [count] occurrence of the substring "
+  "[old] will be replaced with [new]. If [count] == -1 all the occurrence "
+  "will be replaced.") {
+
+  if (!pkCheckArgcRange(vm, ARGC, 2, 3)) return;
+
+  String *old, *new_;
+  if (!validateArgString(vm, 1, &old)) return;
+  if (!validateArgString(vm, 2, &new_)) return;
+
+  String* self = (String*) AS_OBJ(SELF);
+
+  int64_t count = -1;
+  if (ARGC == 3) {
+    if (!validateInteger(vm, ARG(3), &count, "Argument 3")) return;
+    if (count < 0 && count != -1) {
+      RET_ERR(newString(vm, "count should either be >= 0 or -1"));
+    }
+  }
+
+  RET(VAR_OBJ(stringReplace(vm, self, old, new_, (int32_t) count)));
+}
+
+DEF(_stringSplit,
+  "String.split(sep:String) -> List\n"
+  "Split the string into a list of string seperated by [sep] delimeter.") {
+
+  String* sep;
+  if (!validateArgString(vm, 1, &sep)) return;
+
+  if (sep->length == 0) {
+    RET_ERR(newString(vm, "Cannot use empty string as a seperator."));
+  }
+
+  RET(VAR_OBJ(stringSplit(vm, (String*)AS_OBJ(SELF), sep)));
+}
+
+DEF(_stringStrip,
+  "String.strip() -> String\n"
+  "Returns a copy of the string where the leading and trailing whitespace "
+  "removed.") {
+  RET(VAR_OBJ(stringStrip(vm, (String*) AS_OBJ(SELF))));
+}
+
+DEF(_stringLower,
+  "String.lower() -> String\n"
+  "Returns a copy of the string where all the characters are converted to "
+  "lower case letters.") {
+  RET(VAR_OBJ(stringLower(vm, (String*) AS_OBJ(SELF))));
+}
+
+DEF(_stringUpper,
+  "String.lower() -> String\n"
+  "Returns a copy of the string where all the characters are converted to "
+  "upper case letters.") {
+  RET(VAR_OBJ(stringUpper(vm, (String*) AS_OBJ(SELF))));
+}
+
+DEF(_stingStartswith,
+  "String.startswith(prefix: String | List) -> Bool\n"
+  "Returns true if the string starts the specified prefix.") {
+
+  Var prefix = ARG(1);
+  String* self = (String*) AS_OBJ(SELF);
+
+  if (IS_OBJ_TYPE(prefix, OBJ_STRING)) {
+    String* pre = (String*) AS_OBJ(prefix);
+    if (pre->length > self->length) RET(VAR_FALSE);
+    RET(VAR_BOOL((strncmp(self->data, pre->data, pre->length) == 0)));
+
+  } else if (IS_OBJ_TYPE(prefix, OBJ_LIST)) {
+
+    List* prefixes = (List*) AS_OBJ(prefix);
+    for (uint32_t i = 0; i < prefixes->elements.count; i++) {
+      Var pre_var = prefixes->elements.data[i];
+      if (!IS_OBJ_TYPE(pre_var, OBJ_STRING)) {
+        RET_ERR(newString(vm, "Expected a String for prefix."));
+      }
+      String* pre = (String*) AS_OBJ(pre_var);
+      if (pre->length > self->length) RET(VAR_FALSE);
+      if (strncmp(self->data, pre->data, pre->length) == 0) RET(VAR_TRUE);
+    }
+    RET(VAR_FALSE);
+
+  } else {
+    RET_ERR(newString(vm, "Expected a String or a List of prifiexes."));
+  }
+}
+
+DEF(_stingEndswith,
+  "String.endswith(suffix: String | List) -> Bool\n"
+  "Returns true if the string ends with the specified suffix.") {
+
+  Var suffix = ARG(1);
+  String* self = (String*)AS_OBJ(SELF);
+
+  if (IS_OBJ_TYPE(suffix, OBJ_STRING)) {
+    String* suf = (String*)AS_OBJ(suffix);
+    if (suf->length > self->length) RET(VAR_FALSE);
+
+    const char* start = (self->data + (self->length - suf->length));
+    RET(VAR_BOOL((strncmp(start, suf->data, suf->length) == 0)));
+
+  } else if (IS_OBJ_TYPE(suffix, OBJ_LIST)) {
+
+    List* suffixes = (List*)AS_OBJ(suffix);
+    for (uint32_t i = 0; i < suffixes->elements.count; i++) {
+      Var suff_var = suffixes->elements.data[i];
+      if (!IS_OBJ_TYPE(suff_var, OBJ_STRING)) {
+        RET_ERR(newString(vm, "Expected a String for suffix."));
+      }
+      String* suf = (String*)AS_OBJ(suff_var);
+      if (suf->length > self->length) RET(VAR_FALSE);
+
+      const char* start = (self->data + (self->length - suf->length));
+      if (strncmp(start, suf->data, suf->length) == 0) RET(VAR_TRUE);
+    }
+    RET(VAR_FALSE);
+
+  } else {
+    RET_ERR(newString(vm, "Expected a String or a List of suffixes."));
+  }
+}
+
 DEF(_listAppend,
   "List.append(value:var) -> List\n"
-  "Append the [value] to the list and return the list.") {
+  "Append the [value] to the list and return the List.") {
 
   ASSERT(IS_OBJ_TYPE(SELF, OBJ_LIST), OOPS);
 
@@ -860,6 +966,118 @@ DEF(_listAppend,
   RET(SELF);
 }
 
+DEF(_listInsert,
+  "List.insert(index:Number, value:var) -> null\n"
+  "Insert the element at the given index. The index should be "
+  "0 <= index <= list.length.") {
+
+  List* self = (List*)AS_OBJ(SELF);
+
+  int64_t index;
+  if (!validateInteger(vm, ARG(1), &index, "Argument 1")) return;
+
+  if (index < 0 || index > self->elements.count) {
+    RET_ERR(newString(vm, "List.insert index out of bounds."));
+  }
+
+  listInsert(vm, self, (uint32_t) index, ARG(2));
+}
+
+DEF(_listPop,
+  "List.pop(index=-1) -> var\n"
+  "Removes the last element of the list and return it.") {
+
+  ASSERT(IS_OBJ_TYPE(SELF, OBJ_LIST), OOPS);
+  List* self = (List*) AS_OBJ(SELF);
+
+  if (!pkCheckArgcRange(vm, ARGC, 0, 1)) return;
+
+  if (self->elements.count == 0) {
+    RET_ERR(newString(vm, "Cannot pop from an empty list."));
+  }
+
+  int64_t index = -1;
+  if (ARGC == 1) {
+    if (!validateInteger(vm, ARG(1), &index, "Argument 1")) return;
+  }
+  if (index < 0) index = self->elements.count + index;
+
+  if (index < 0 || index >= self->elements.count) {
+    RET_ERR(newString(vm, "List.pop index out of bounds."));
+  }
+  RET(listRemoveAt(vm, self, (uint32_t) index));
+}
+
+DEF(_listFind,
+  "List.find(value:var) -> Number\n"
+  "Find the value and return its index. If the vlaue not exists "
+  "it'll return -1.") {
+
+  ASSERT(IS_OBJ_TYPE(SELF, OBJ_LIST), OOPS);
+  List* self = (List*)AS_OBJ(SELF);
+
+  Var* it = self->elements.data;
+  if (it == NULL) RET(VAR_NUM(-1)); // Empty list.
+
+  for (; it < self->elements.data + self->elements.count; it++) {
+    if (isValuesEqual(*it, ARG(1))) {
+      RET(VAR_NUM((double) (it - self->elements.data)));
+    }
+  }
+
+  RET(VAR_NUM(-1));
+}
+
+DEF(_listClear,
+  "List.clear() -> null\n"
+  "Removes all the entries in the list.") {
+  listClear(vm, (List*) AS_OBJ(SELF));
+}
+
+DEF(_mapClear,
+  "Map.clear() -> null\n"
+  "Removes all the entries in the map.") {
+  Map* self = (Map*) AS_OBJ(SELF);
+  mapClear(vm, self);
+}
+
+DEF(_mapGet,
+  "Map.get(key:var, default=null) -> var\n"
+  "Returns the key if its in the map, otherwise the default value will "
+  "be returned.") {
+
+  if (!pkCheckArgcRange(vm, ARGC, 1, 2)) return;
+
+  Var default_ = (ARGC == 1) ? VAR_NULL : ARG(2);
+
+  Map* self = (Map*) AS_OBJ(SELF);
+
+  Var value = mapGet(self, ARG(1));
+  if (IS_UNDEF(value)) RET(default_);
+  RET(value);
+}
+
+DEF(_mapHas,
+  "Map.has(key:var) -> Bool\n"
+  "Returns true if the key exists.") {
+
+  Map* self = (Map*)AS_OBJ(SELF);
+  Var value = mapGet(self, ARG(1));
+  RET(VAR_BOOL(!IS_UNDEF(value)));
+}
+
+DEF(_mapPop,
+  "Map.pop(key:var) -> var\n"
+  "Pops the value at the key and return it.") {
+
+  Map* self = (Map*)AS_OBJ(SELF);
+  Var value = mapRemoveKey(vm, self, ARG(1));
+  if (IS_UNDEF(value)) {
+    RET_ERR(stringFormat(vm, "Key '@' does not exists.", toRepr(vm, ARG(1))));
+  }
+  RET(value);
+}
+
 DEF(_fiberRun,
   "Fiber.run(...) -> var\n"
   "Runs the fiber's function with the provided arguments and returns it's "
@@ -951,7 +1169,27 @@ static void initializePrimitiveClasses(PKVM* vm) {
   ADD_METHOD(PK_NUMBER, "times",  _numberTimes,     1);
   ADD_METHOD(PK_NUMBER, "isint",  _numberIsint,     0);
   ADD_METHOD(PK_NUMBER, "isbyte", _numberIsbyte,    0);
+
+  ADD_METHOD(PK_STRING, "strip",   _stringStrip,    0);
+  ADD_METHOD(PK_STRING, "lower",   _stringLower,    0);
+  ADD_METHOD(PK_STRING, "upper",   _stringUpper,    0);
+  ADD_METHOD(PK_STRING, "find",    _stringFind,    -1);
+  ADD_METHOD(PK_STRING, "replace", _stringReplace, -1);
+  ADD_METHOD(PK_STRING, "split",   _stringSplit,    1);
+  ADD_METHOD(PK_STRING, "startswith", _stingStartswith, 1);
+  ADD_METHOD(PK_STRING, "endswith", _stingEndswith, 1);
+
+  ADD_METHOD(PK_LIST,   "clear",  _listClear,      0);
+  ADD_METHOD(PK_LIST,   "find",   _listFind,       1);
   ADD_METHOD(PK_LIST,   "append", _listAppend,     1);
+  ADD_METHOD(PK_LIST,   "pop",    _listPop,       -1);
+  ADD_METHOD(PK_LIST,   "insert", _listInsert,     2);
+
+  ADD_METHOD(PK_MAP,    "clear",  _mapClear,       0);
+  ADD_METHOD(PK_MAP,    "get",    _mapGet,        -1);
+  ADD_METHOD(PK_MAP,    "has",    _mapHas,         1);
+  ADD_METHOD(PK_MAP,    "pop",    _mapPop,         1);
+
   ADD_METHOD(PK_FIBER,  "run",    _fiberRun,      -1);
   ADD_METHOD(PK_FIBER,  "resume", _fiberResume,   -1);
 
@@ -1351,7 +1589,11 @@ bool varContains(PKVM* vm, Var elem, Var container) {
       String* str = (String*) AS_OBJ(container);
       if (sub->length > str->length) return false;
 
-      TODO;
+      // FIXME: strstr function can only be used for null terminated strings.
+      // But pocket lang strings can contain any byte values including a null
+      // byte \x00.
+      const char* match = strstr(str->data, sub->data);
+      return match != NULL;
 
     } break;
 
@@ -1419,15 +1661,6 @@ Var varGetAttrib(PKVM* vm, Var on, String* attrib) {
 
         case CHECK_HASH("length", 0x83d03615):
           return VAR_NUM((double)(str->length));
-
-        case CHECK_HASH("lower", 0xb51d04ba):
-          return VAR_OBJ(stringLower(vm, str));
-
-        case CHECK_HASH("upper", 0xa8c6a47):
-          return VAR_OBJ(stringUpper(vm, str));
-
-        case CHECK_HASH("strip", 0xfd1b18d1):
-          return VAR_OBJ(stringStrip(vm, str));
       }
     } break;
 
@@ -1441,10 +1674,7 @@ Var varGetAttrib(PKVM* vm, Var on, String* attrib) {
     } break;
 
     case OBJ_MAP: {
-      // map = { "foo" : 42, "can't access" : 32 }
+      // TODO:
-      // val = map.foo ## <-- This should be error
-      // Only the map's attributes are accessed here.
-      TODO;
     } break;
 
     case OBJ_RANGE: {
@@ -1509,7 +1739,7 @@ Var varGetAttrib(PKVM* vm, Var on, String* attrib) {
     } break;
 
     case OBJ_CLASS:
-      TODO;
+      // TODO:
       break;
 
     case OBJ_INST: {

src/core/value.c

@@ -23,6 +23,9 @@
 // capacity by the GROW_FACTOR.
 #define GROW_FACTOR 2
 
+#define _MAX(a,b) ((a) > (b) ? (a) : (b))
+#define _MIN(a,b) ((a) < (b) ? (a) : (b))
+
 // Buffer implementations.
 DEFINE_BUFFER(Uint, uint32_t)
 DEFINE_BUFFER(Byte, uint8_t)
@@ -608,6 +611,139 @@ String* stringStrip(PKVM* vm, String* self) {
   return newStringLength(vm, start, (uint32_t)(end - start + 1));
 }
 
+String* stringReplace(PKVM* vm, String* self,
+                      String* old, String* new_, int32_t count) {
+  // The algorithm:
+  //
+  // We'll first deduce the maximum possible occurence of the old string.
+  //
+  //   max_count = floor(self.length / old.length)
+  //
+  // If count == -1 we'll set it to max_count, otherwise we can update our
+  // count as follows.
+  //
+  //   count = min(count, min_count)
+  //
+  // Now we know the maximum possible length of the new string.
+  //
+  //   length = max(self.length,
+  //                self.length + (new.length - old.length) * count)
+  //
+  // Finally we use "C" functions strstr() and memcpy() to find and replace.
+
+  // FIXME: this function use strstr() which only supports null terminated
+  // strings, if our string contain any \x00 the replacement will stop.
+
+  ASSERT(count >= 0 || count == -1, OOPS);
+
+  // Optimize case.
+  if (self->length == 0 || old->length == 0 || count == 0) return self;
+  if (IS_STR_EQ(old, new_)) return self;
+
+  int32_t max_count = self->length / old->length;
+  count = (count == -1)
+    ? max_count
+    : _MIN(count, max_count);
+
+  // TODO: New length can be overflow if the string is too large
+  // we should handle it here.
+
+  uint32_t length = _MAX(self->length,
+                    self->length + (new_->length - old->length) * count);
+
+  String* replaced = self; // Will be allocated if any match found.
+  int32_t replacedc = 0; // Replaced count so far.
+
+  const char* s = self->data; // Source: current position in self.
+  char* d = NULL; // Destination pointer in replaced.
+
+  do {
+    if (replacedc == count) break;
+
+    const char* match = strstr(s, old->data);
+    if (match == NULL) break;
+
+    // Note that since we're not allocating anything else here, this string
+    // doesn't needs to pushed to VM's temp references.
+    if (replacedc == 0) {
+      replaced = newStringLength(vm, "", length);
+      d = replaced->data;
+    }
+
+    // Copy everything from [s] till [match].
+    memcpy(d, s, match - s);
+    d += match - s;
+    s = match;
+
+    // Copy the replace string.
+    memcpy(d, new_->data, new_->length);
+    d += new_->length;
+    s += old->length;
+    replacedc++;
+
+  } while (true);
+
+  // Copy the rest of the string from [s] till the end.
+  if (d != NULL) {
+    uint32_t tail_length = self->length - (int32_t) (s - self->data);
+    memcpy(d, s, tail_length);
+    d += tail_length;
+
+    // Update the string.
+    replaced->length = (int32_t) (d - replaced->data);
+    ASSERT(replaced->length < replaced->capacity, OOPS);
+    replaced->data[replaced->length] = '\0';
+    replaced->hash = utilHashString(replaced->data);
+
+  } else {
+    ASSERT(self == replaced, OOPS);
+  }
+
+  return replaced;
+}
+
+List* stringSplit(PKVM* vm, String* self, String* sep) {
+
+  ASSERT(sep->length != 0, OOPS);
+
+  const char* s = self->data; // Current position in self.
+
+  List* list = newList(vm, 0);
+  vmPushTempRef(vm, &list->_super); // list.
+  do {
+    const char* match = strstr(s, sep->data);
+    if (match == NULL) {
+
+      // Add the tail string from [s] till the end. Optimize case: if the
+      // string doesn't have any match we can reuse self.
+      if (s == self->data) {
+        ASSERT(list->elements.count == 0, OOPS);
+        listAppend(vm, list, VAR_OBJ(self));
+
+      } else {
+        String* tail = newStringLength(vm, s,
+          (uint32_t)(self->length - (s - self->data)));
+        vmPushTempRef(vm, &tail->_super); // tail.
+        listAppend(vm, list, VAR_OBJ(tail));
+        vmPopTempRef(vm); // tail.
+      }
+
+      break; // We're done.
+    }
+
+    String* split = newStringLength(vm, s, (uint32_t)(match - s));
+    vmPushTempRef(vm, &split->_super); // split.
+    listAppend(vm, list, VAR_OBJ(split));
+    vmPopTempRef(vm); // split.
+
+    s = match + sep->length;
+
+  } while (true);
+  vmPopTempRef(vm); // list.
+
+  return list;
+}
+
 String* stringFormat(PKVM* vm, const char* fmt, ...) {
   va_list arg_list;
 
@@ -698,6 +834,8 @@ void listInsert(PKVM* vm, List* self, uint32_t index, Var value) {
 }
 
 Var listRemoveAt(PKVM* vm, List* self, uint32_t index) {
+  ASSERT_INDEX(index, self->elements.count);
+
   Var removed = self->elements.data[index];
   if (IS_OBJ(removed)) vmPushTempRef(vm, AS_OBJ(removed));
 
@@ -720,6 +858,10 @@ Var listRemoveAt(PKVM* vm, List* self, uint32_t index) {
   return removed;
 }
 
+void listClear(PKVM* vm, List* self) {
+  pkVarBufferClear(&self->elements, vm);
+}
+
 List* listAdd(PKVM* vm, List* l1, List* l2) {
 
   // Optimize end case.
@@ -898,7 +1040,7 @@ void mapClear(PKVM* vm, Map* self) {
 
 Var mapRemoveKey(PKVM* vm, Map* self, Var key) {
   MapEntry* entry;
-  if (!_mapFindEntry(self, key, &entry)) return VAR_NULL;
+  if (!_mapFindEntry(self, key, &entry)) return VAR_UNDEFINED;
 
   // Set the key as VAR_UNDEFINED to mark is as an available slow and set it's
   // value to VAR_TRUE for tombstone.
@@ -1609,3 +1751,7 @@ bool toBool(Var v) {
   UNREACHABLE();
   return false;
 }
+
+// Undefining for amalgamation to let othre libraries also define _MIN, _MAX.
+#undef _MAX
+#undef _MIN

src/core/value.h

@@ -643,6 +643,16 @@ String* stringUpper(PKVM* vm, String* self);
 // If the string is already trimmed it'll return the same string.
 String* stringStrip(PKVM* vm, String* self);
 
+// Replace the [count] occurence of the [old] string with [new_] string. If
+// [count] == -1. It'll replace all the occurences. If nothing is replaced
+// the original string will be returned.
+String* stringReplace(PKVM* vm, String* self,
+                      String* old, String* new_, int count);
+
+// Split the string into a list of string separated by [sep]. String [sep] must
+// not be of length 0 otherwise an assertion will fail.
+List* stringSplit(PKVM* vm, String* self, String* sep);
+
 // Creates a new string from the arguments. This is intended for internal
 // usage and it has 2 formated characters (just like wren does).
 // $ - a C string
@@ -672,6 +682,9 @@ void listInsert(PKVM* vm, List* self, uint32_t index, Var value);
 // Remove and return element at [index].
 Var listRemoveAt(PKVM* vm, List* self, uint32_t index);
 
+// Remove all the elements of the list.
+void listClear(PKVM* vm, List* self);
+
 // Create a new list by joining the 2 given list and return the result.
 List* listAdd(PKVM* vm, List* l1, List* l2);
 
@@ -686,7 +699,7 @@ void mapSet(PKVM* vm, Map* self, Var key, Var value);
 void mapClear(PKVM* vm, Map* self);
 
 // Remove the [key] from the map. If the key exists return it's value
-// otherwise return VAR_NULL.
+// otherwise return VAR_UNDEFINED.
 Var mapRemoveKey(PKVM* vm, Map* self, Var key);
 
 // Returns true if the fiber has error, and if it has any the fiber cannot be

tests/lang/builtin_ty.pk

@@ -5,6 +5,10 @@
 ## Number
 ###############################################################################
 
+assert(hex(12648430) == '0xc0ffee')
+assert(hex(255) == '0xff' and hex(10597059) == '0xa1b2c3')
+assert(hex(-4294967295) == '-0xffffffff') ## the largest.
+
 sum = 0
 5.times fn(i)
   sum += i
@@ -15,10 +19,27 @@ assert(Number("-.23e+6") == -.23e6)
 assert(Number("0b10100101") == 0b10100101)
 assert(Number("-0Xabcdef123") == -0xabcdef123)
 
+###############################################################################
+## RANGE
+###############################################################################
+
+r = 1..5
+assert(r.as_list == [1, 2, 3, 4])
+assert(r.first == 1)
+assert(r.last == 5)
+
 ###############################################################################
 ## STRING
 ###############################################################################
 
+assert(''.length == 0)
+assert('test'.length == 4)
+assert(''.lower() == '' and ''.upper() == '')
+assert('already+lower '.lower() == 'already+lower ')
+assert('ALREADY+UPPER '.upper() == 'ALREADY+UPPER ')
+assert('tEST+InG'.lower() == 'test+ing')
+assert('tEST+InG'.upper() == 'TEST+ING')
+
 s = "foobar"
 assert(s[-3] == 'b')
 
@@ -33,6 +54,39 @@ assert("abcd"[-1..-3] == "dcb")
 assert(""[0..-1] == "")
 assert(""[-1..0] == "")
 
+assert(' trim '.strip() == 'trim')
+assert(''.strip() == '')
+
+lorem = "\
+Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor 
+incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nost
+rud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis 
+aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fug
+iat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in cu
+lpa qui officia deserunt mollit anim id est laborum."
+
+assert("sint" in lorem)
+ut = lorem.find('ut'); assert(ut != -1)
+assert(lorem[ut+3 .. ut+8] == 'labore')
+
+assert("foobar".replace("foo", "baz") == "bazbar")
+assert("abcdefabdcefabaeef".replace("ab", "") == "cdefdcefaeef")
+assert("xx.xx.xx.xx".replace("xx", "yy", 2) == "yy.yy.xx.xx")
+assert("aaaaaaaaaaaaa".replace('a', '!b', 5) == "!b!b!b!b!baaaaaaaa")
+assert("aaaaaaaaaaaaa".replace('a', 'b', 1000) == "bbbbbbbbbbbbb")
+
+assert("a,b,c".split(',') == ['a', 'b', 'c'])
+assert('a,'.split(',') == ['a', ''])
+assert('foo!!bar!!baz'.split('!!') == ['foo', 'bar', 'baz'])
+
+assert('abcdef'.startswith('abc'))
+assert(not 'x'.startswith('abc'))
+assert(not 'pqr'.startswith(['abc', 'def', 'gh']))
+
+assert('foobar'.endswith('obar'))
+assert(not 'foobar'.endswith('rfoo'))
+assert('image.png'.endswith(['.jpg', '.jpeg', '.png', '.ppm']))
+
 ###############################################################################
 ## LIST
 ###############################################################################
@@ -52,6 +106,67 @@ assert(l[-1..-3] == [4, 3, 2])
 assert([][0..0] == [])
 assert([][-1..-1] == [])
 
+assert([].length == 0)
+assert([1, 2, 3].length == 3)
+
+assert(['a'].append('b') == ['a', 'b'])
+
+assert(l.find(2) == 1)
+assert(l.find(4) == 3)
+assert(l.find(7) == -1)
+
+assert(l.pop(-2) == 3 and l == [1, 2, 4])
+assert(l.pop() == 4)
+assert(l.pop() == 2)
+assert(l == [1])
+
+l = []
+l.insert(0, 'l')
+l.insert(1, 'l')
+l.insert(0, 'h')
+l.insert(3, 'o')
+l.insert(1, 'e')
+assert(l == ['h', 'e', 'l', 'l', 'o'])
+
+###############################################################################
+## MAP
+###############################################################################
+
+swtich = {
+  0 : fn return 1 end,
+  1 : fn return 2 end,
+  2 : fn return 3 end,
+  3 : fn return 4 end,
+  4 : fn return 5 end,
+}
+
+for i in 0..5
+  assert(swtich.get(i)() == i+1)
+end
+
+vars = {
+  'os' : 'mint',
+  'version' : '20.3',
+  'name' : 'Una',
+}
+
+assert(vars.get('os') == 'mint')
+assert(vars.get('family', 'linux') == 'linux')
+assert(vars.has('version'))
+assert(!vars.has('build'))
+
+
+###############################################################################
+## FUNCTIONS
+###############################################################################
+
+assert(print.arity == -1)
+assert(hex.arity == 1)
+assert(fn(a, b)end .arity == 2)
+assert(print.name == "print")
+def foo(p1, p2, p3) end
+assert(foo.name == "foo")
+assert(foo.arity == 3)
 
 ## If we got here, that means all test were passed.
 print('All TESTS PASSED')

tests/lang/core.pk

@@ -1,50 +0,0 @@
-## Core builtin functions and attribute tests.
-
-assert(hex(12648430) == '0xc0ffee')
-assert(hex(255) == '0xff' and hex(10597059) == '0xa1b2c3')
-assert(hex(-4294967295) == '-0xffffffff') ## the largest.
-
-## string attributes.
-assert(''.length == 0)
-assert('test'.length == 4)
-assert(''.lower == '' and ''.upper == '')
-assert('already+lower '.lower == 'already+lower ')
-assert('ALREADY+UPPER '.upper == 'ALREADY+UPPER ')
-assert('tEST+InG'.lower == 'test+ing')
-assert('tEST+InG'.upper == 'TEST+ING')
-
-assert(' trim '.strip == 'trim')
-assert(''.strip == '')
-
-## List attribute
-assert([].length == 0)
-assert([1, 2, 3].length == 3)
-
-## Function
-assert(print.arity == -1)
-assert(hex.arity == 1)
-assert(fn(a, b)end .arity == 2)
-assert(print.name == "print")
-def foo(p1, p2, p3) end
-assert(foo.name == "foo")
-assert(foo.arity == 3)
-
-## String functions
-assert(str_sub('c programming', 2, 11) == 'programming')
-assert(str_sub('foobarbaz', 2, 3) == 'oba')
-assert(str_sub('abcdef', 1, 2) == 'bc')
-assert(str_sub('I am a boy', 0, 4) == 'I am')
-assert(str_sub('programming', 2, 0) == '')
-assert(str_sub('foobar', 5, 0) == '')
-assert(str_sub('foobar', 0, 6) == 'foobar')
-assert(str_sub('', 0, 0) == '')
-
-## range
-r = 1..5
-assert(r.as_list == [1, 2, 3, 4])
-assert(r.first == 1)
-assert(r.last == 5)
-
-# If we got here, that means all test were passed.
-print('All TESTS PASSED')
-