Depth check

docs/TODO.txt

@@ -33,18 +33,18 @@ DONE: Assertion-based test scripts
 DONE: Import/export keywords
 DONE: A way to check the type of a variable (typeOf keyword)
 DONE: slice and dot notation around the builtin _index and _dot functions
+DONE: maximum recursion/function depth
 
 
+TODO: nested compound assignment
+TODO: better sugar for _push and _pop
 TODO: ternary operator
 TODO: Nullish types?
 TODO: hooks on the external libraries, triggered on import
 TODO: standard library
 TODO: external script runner library
 TODO: document how it all works - book?
-TODO: maximum recursion/function depth
 TODO: better API
-TODO: better sugar for _push and _pop
-TODO: nested compound assignment
 TODO: packaging for release?
 
 NOPE: a = b = c = 1;

scripts/small.toy

@@ -1,25 +1,10 @@
 
 
 
+fn loop(count) {
+	print count++;
 
-fn makeCounter() {
+	loop(count);
-	var total: int = 0;
-
-	fn counter(): int {
-		return ++total;
-	}
-
-	return counter;
 }
 
-var tally = makeCounter();
+loop(0);
-
-print tally(); //1
-print tally(); //2
-print tally(); //3
-
-export tally;
-
-//heck yeah!
-import tally as tally2;
-print tally2(); //4

source/interpreter.c

@@ -991,6 +991,13 @@ static void execInterpreter(Interpreter*);
 static void readInterpreterSections(Interpreter* interpreter);
 
 static bool execFnCall(Interpreter* interpreter) {
+	//BUGFIX: depth check - don't drown!
+	if (interpreter->depth >= 1000) {
+		interpreter->errorOutput("Depth check failed\n");
+		interpreter->panic = true;
+		return false;
+	}
+
 	LiteralArray arguments;
 	initLiteralArray(&arguments);
 
@@ -1057,6 +1064,7 @@ static bool execFnCall(Interpreter* interpreter) {
 	inner.length = func.as.function.length;
 	inner.count = 0;
 	inner.codeStart = -1;
+	inner.depth = interpreter->depth + 1;
 	inner.panic = false;
 	initLiteralArray(&inner.stack);
 	inner.exports = interpreter->exports;
@@ -2368,6 +2376,7 @@ void runInterpreter(Interpreter* interpreter, unsigned char* bytecode, int lengt
 
 	initLiteralArray(&interpreter->stack);
 
+	interpreter->depth = 0;
 	interpreter->panic = false;
 
 	//prep the bytecode

source/interpreter.h

@@ -27,6 +27,7 @@ typedef struct Interpreter {
 	PrintFn assertOutput;
 	PrintFn errorOutput;
 
+	int depth; //don't overflow
 	bool panic;
 } Interpreter;