(or... )

build.hxml

@@ -1,4 +1,6 @@
 -cp src
+-lib hscript
+-lib uuid
 --macro nullSafety("kiss", Strict)
 --main kiss.Main
 --interp

src/kiss/Macros.hx

@@ -4,9 +4,11 @@ import haxe.macro.Expr;
 import haxe.macro.Context;
 import hscript.Parser;
 import hscript.Interp;
+import uuid.Uuid;
 import kiss.Reader;
 import kiss.Kiss;
 
+using uuid.Uuid;
 using kiss.Reader;
 using kiss.Helpers;
 
@@ -53,6 +55,25 @@ class Macros {
 
         macros["cond"] = cond;
 
+        // (or... ) uses (cond... ) under the hood
+        macros["or"] = (args:Array<ReaderExp>, k) -> {
+            var uniqueVarName = "_" + Uuid.v4().toShort();
+            var uniqueVarSymbol = Symbol(uniqueVarName).withPos(args[0].pos);
+
+            CallExp(Symbol("begin").withPos(args[0].pos), [
+                CallExp(Symbol("deflocal").withPos(args[0].pos), [
+                    TypedExp("Any", uniqueVarSymbol).withPos(args[0].pos),
+                    Symbol("null").withPos(args[0].pos)
+                ]).withPos(args[0].pos),
+                CallExp(Symbol("cond").withPos(args[0].pos), [
+                    for (arg in args) {
+                        CallExp(CallExp(Symbol("set").withPos(args[0].pos), [uniqueVarSymbol, arg]).withPos(args[0].pos),
+                            [uniqueVarSymbol]).withPos(args[0].pos);
+                    }
+                ]).withPos(args[0].pos)
+            ]).withPos(args[0].pos);
+        };
+
         // Under the hood, (defmacrofun ...) defines a runtime function that accepts Quote arguments and a special form that quotes the arguments to macrofun calls
         macros["defmacrofun"] = (exps:Array<ReaderExp>, k:KissState) -> {
             if (exps.length < 3)

src/test/cases/BasicTestCase.hx

@@ -164,4 +164,8 @@ class BasicTestCase extends Test {
         Assert.equals("this", BasicTestCase.myCond3);
         Assert.equals(null, BasicTestCase.myCondFallthrough);
     }
+
+    function testOr() {
+        Assert.equals(5, BasicTestCase.myOr1);
+    }
 }

src/test/cases/BasicTestCase.kiss

@@ -122,4 +122,6 @@
     (true "default")))
 
 (defvar myCondFallthrough (cond
-    (false "not this")))
+    (false "not this")))
+
+(defvar myOr1 (or null 5))