Fixed some indexing bugs

README.md

@@ -8,6 +8,15 @@ This is the Toy programming language interpreter, written in C.
 
 Special thanks to http://craftinginterpreters.com/ for their fantastic book that set me on this path.
 
+## Nifty Features
+
+* Simple C-like syntax
+* Bytecode intermediate compilation
+* `import` and `export` variables from the host program
+* Optional, but robust type system
+* functions and types are first-class citizens
+* Fancy slice notation for strings, arrays and dictionaries (`print greeting[0:4:-1]; //prints "olleh"`)
+
 ## Building
 
 Simply run make in the root directory.
@@ -15,7 +24,7 @@ Simply run make in the root directory.
 ## Syntax
 
 ```
-import "standard"; //for a bunch of utility functions
+import standard; //for a bunch of utility functions
 
 
 print "Hello world"; //"print" is a keyword
@@ -36,13 +45,13 @@ fn makeCounter() { //declare a function like this
 	return counter; //closures are explicitly supported
 }
 
-var counter = makeCounter();
+var tally = makeCounter();
 
-print counter(); //1
-print counter(); //2
-print counter(); //3
+print tally(); //1
+print tally(); //2
+print tally(); //3
 
-export makeCounter; //export this variable to the host program
+export tally; //export this variable to the host program
 ```
 
 # License

scripts/small.toy

@@ -2,14 +2,24 @@
 
 
 
-var t: type = astype [int];
-var u: type = astype [t];
+fn makeCounter() {
+	var total: int = 0;
 
-var a: u;
+	fn counter(): int {
+		return ++total;
+	}
 
-t = astype [float]; //redefnition
+	return counter;
+}
 
-var b: u;
+var tally = makeCounter();
 
-print typeof a; //<[<int>]>
-print typeof b; //<[<float>]>
+print tally(); //1
+print tally(); //2
+print tally(); //3
+
+export tally;
+
+//heck yeah!
+import tally as tally2;
+print tally2(); //4

scripts/test/index-arrays.toy

@@ -1,8 +1,22 @@
+
+//test basic indexing
+{
+	var week = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"];
+
+	assert week[1] == "tuesday", "basic indexing failed (single element)";
+
+	assert week[1:1] == ["tuesday"], "basic indexing failed (single element as array)";
+
+	assert week[:] == ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"], "basic default indexing failed (first and second)";
+	assert week[::] == ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"], "basic default indexing failed (first, second and third)";
+}
+
+
 //test basic replacement
 {
 	var week = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"];
 
-	week[3] = "Holiday";
+	week[3:3] = "Holiday";
 
 	assert week == ["monday", "tuesday", "wednesday", "Holiday", "friday", "saturday", "sunday"], "basic replacement failed";
 }

scripts/test/index-strings.toy

@@ -1,13 +1,24 @@
-//test basic replacement
+//test basic indexing
 var greeting: string = "hello world";
 
+assert greeting[1] == "e", "basic default index failed (first)";
+
+assert greeting[:] == "hello world", "basic default index failed (first and second)";
+
+assert greeting[::] == "hello world", "basic default index failed (first, second & third)";
+
+assert greeting[0:4] == "hello", "basic indexing failed";
+
+
+
+//test basic replacement
 greeting[0:4] = "goodnight";
 
 assert greeting == "goodnight world", "basic replacement failed";
 
-
 //test backwards string
 assert greeting[::-1] == "dlrow thgindoog", "backwards string failed";
+assert greeting[11:15:-1] == "dlrow", "backwards indexed string failed";
 
 
 //test string weird manipulation

source/interpreter.c

@@ -1386,7 +1386,7 @@ static bool execIndex(Interpreter* interpreter) {
 		freeLiteral(second);
 		freeLiteral(first);
 		freeLiteral(compound);
-		freeLiteral(idn);
+		//freeLiteral(idn); //since compound is freed, idn is still pointing there
 		return false;
 	}
 

source/lib_builtin.c

@@ -329,7 +329,7 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 			if (!IS_NULL(second)) {
 				if (IS_BOOLEAN(second)) {
 					freeLiteral(second);
-					second = TO_INTEGER_LITERAL(AS_ARRAY(compound)->count);
+					second = TO_INTEGER_LITERAL(AS_ARRAY(compound)->count - 1);
 				}
 			}
 
@@ -387,10 +387,10 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 			LiteralArray* result = ALLOCATE(LiteralArray, 1);
 			initLiteralArray(result);
 
-			int min = AS_INTEGER(third) > 0 ? 0 : AS_INTEGER(second) - 1;
+			int min = AS_INTEGER(third) > 0 ? AS_INTEGER(first) : AS_INTEGER(second);
 
 			//copy compound into result
-			for (int i = min; i >= 0 && i <= AS_ARRAY(compound)->count && i >= AS_INTEGER(first) && i < AS_INTEGER(second); i += AS_INTEGER(third)) {
+			for (int i = min; i >= 0 && i <= AS_ARRAY(compound)->count && i >= AS_INTEGER(first) && i <= AS_INTEGER(second); i += AS_INTEGER(third)) {
 				Literal idx = TO_INTEGER_LITERAL(i);
 				Literal tmp = getLiteralArray(AS_ARRAY(compound), idx);
 				pushLiteralArray(result, tmp);
@@ -417,7 +417,7 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 			if (!IS_NULL(second)) {
 				if (IS_BOOLEAN(second)) {
 					freeLiteral(second);
-					second = TO_INTEGER_LITERAL(AS_ARRAY(compound)->count);
+					second = TO_INTEGER_LITERAL(AS_INTEGER(first));
 				}
 			}
 
@@ -487,6 +487,7 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 
 				int min = AS_INTEGER(third) > 0 ? 0 : AS_ARRAY(assign)->count - 1;
 
+				if (IS_ARRAY(assign)) { //push elements of an assigned array
 					for (int i = min; i >= 0 && i < AS_ARRAY(assign)->count; i += AS_INTEGER(third)) {
 						Literal idx = TO_INTEGER_LITERAL(i);
 						Literal tmp = getLiteralArray(AS_ARRAY(assign), idx); //backwards
@@ -497,6 +498,10 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 						freeLiteral(idx);
 						freeLiteral(tmp);
 					}
+				}
+				else { //push just one element into the array
+					pushLiteralArray(result, assign);
+				}
 
 				for (int i = AS_INTEGER(second) + 1; i < AS_ARRAY(compound)->count; i++) {
 					Literal idx = TO_INTEGER_LITERAL(i);
@@ -649,11 +654,12 @@ int _index(Interpreter* interpreter, LiteralArray* arguments) {
 			//start building a new string from the old one
 			char* result = ALLOCATE(char, MAX_STRING_LENGTH);
 
-			int min = AS_INTEGER(third) > 0 ? AS_INTEGER(first) : AS_INTEGER(second) - 1;
+			int lower = AS_INTEGER(third) > 0 ? AS_INTEGER(first) : AS_INTEGER(first) -1;
+			int min = AS_INTEGER(third) > 0 ? AS_INTEGER(first) : AS_INTEGER(second) -1;
 
 			//copy compound into result
 			int resultIndex = 0;
-			for (int i = min; i >= AS_INTEGER(first) && i < AS_INTEGER(second); i += AS_INTEGER(third)) {
+			for (int i = min; i >= lower && i <= AS_INTEGER(second); i += AS_INTEGER(third)) {
 				result[ resultIndex++ ] = AS_STRING(compound)[ i ];
 			}
 

source/parser.c

@@ -736,17 +736,24 @@ static Opcode indexAccess(Parser* parser, Node** nodeHandle) {
 	emitNodeLiteral(&second, TO_BOOLEAN_LITERAL(true));
 	emitNodeLiteral(&third, TO_BOOLEAN_LITERAL(true));
 
+	bool readFirst = false; //pattern matching is bullcrap
+
 	//eat the first
 	if (!match(parser, TOKEN_COLON)) {
 		freeNode(first);
 		parsePrecedence(parser, &first, PREC_TERNARY);
 		match(parser, TOKEN_COLON);
+		readFirst = true;
 	}
 
 	if (match(parser, TOKEN_BRACKET_RIGHT)) {
+
+		if (readFirst) {
 			freeNode(second);
-		freeNode(third);
 			second = NULL;
+		}
+
+		freeNode(third);
 		third = NULL;
 
 		emitNodeIndex(nodeHandle, first, second, third);