catch a bug in while loops

src/kiss/SpecialForms.hx

@@ -334,7 +334,7 @@ class SpecialForms {
         function whileForm(invert:Bool, wholeExp:ReaderExp, args:Array<ReaderExp>, k:KissState) {
             var funcName = if (invert) "until" else "while";
             var b = wholeExp.expBuilder();
-            var cond = k.convert(b.callSymbol("Prelude.truthy", [args[0]]));
+            var cond = k.convert(b.callSymbol("Prelude.truthy", [args.shift()]));
             if (invert) {
                 cond = macro !$cond;
                 cond = b.haxeExpr(cond);

src/test/cases/BasicTestCase.hx

@@ -355,6 +355,10 @@ class BasicTestCase extends Test {
         _testIntersect();
     }
 
+    function testWhile() {
+        _testWhile();
+    }
+
     function testWhileLet() {
         _testWhileLet();
     }

src/test/cases/BasicTestCase.kiss

@@ -675,6 +675,14 @@ From:[(assert false (+ \"false \" \"should \" \"have \" \"been \" \"true\"))]" m
         )
     (Assert.pass))
 
+(function _testWhile []
+    (let [max 8
+            &mut current 0
+            &mut iterations 0]
+        (while (>= max (+= current 1))
+            (+= iterations 1))
+        (Assert.equals 8 iterations)))
+
 (function _testWhileLet []
     (let [&mut idx 0
             lines ["a" "b" "c"]