diff --git a/src/copapy/__init__.py b/src/copapy/__init__.py
index acf7155..39a4b4e 100644
--- a/src/copapy/__init__.py
+++ b/src/copapy/__init__.py
@@ -18,6 +18,7 @@ uniint: TypeAlias = 'cpint | int'
 unibool: TypeAlias = 'cpbool | bool'
 
 TNumber = TypeVar("TNumber", bound='CPNumber')
+T = TypeVar("T")
 
 
 def get_var_name(var: Any, scope: dict[str, Any] = globals()) -> list[str]:
@@ -355,6 +356,36 @@ def net_from_value(value: Any) -> Net:
     return Net(vi.dtype, vi)
 
 
+@overload
+def iif(expression: CPNumber, true_result: unibool, false_result: unibool) -> cpbool:  # pyright: ignore[reportOverlappingOverload]
+    ...
+
+
+@overload
+def iif(expression: CPNumber, true_result: uniint, false_result: uniint) -> cpint:
+    ...
+
+
+@overload
+def iif(expression: CPNumber, true_result: unifloat, false_result: unifloat) -> cpfloat:
+    ...
+
+
+@overload
+def iif(expression: NumLike, true_result: T, false_result: T) -> T:
+    ...
+
+
+def iif(expression: Any, true_result: Any, false_result: Any) -> Any:
+    # TODO: check that input types are matching
+    alowed_type = cpint | cpfloat | cpbool | int | float | bool
+    assert isinstance(true_result, alowed_type) and isinstance(false_result, alowed_type), "Result type not supported"
+    if isinstance(expression, CPNumber):
+        return (expression != 0) * true_result + (expression == 0) * false_result
+    else:
+        return true_result if expression else false_result
+
+
 def _add_op(op: str, args: list[CPNumber | int | float], commutative: bool = False) -> CPNumber:
     arg_nets = [a if isinstance(a, Net) else net_from_value(a) for a in args]
 
diff --git a/tests/test_ops.py b/tests/test_ops.py
index 115f4aa..8b69f74 100644
--- a/tests/test_ops.py
+++ b/tests/test_ops.py
@@ -1,4 +1,4 @@
-from copapy import cpvalue, Target, NumLike, Net, cpint
+from copapy import cpvalue, Target, NumLike, Net, iif, cpint
 from pytest import approx
 
 
@@ -32,14 +32,21 @@ def function6(c1: NumLike) -> list[NumLike]:
     return [c1 == True]
 
 
-def test_compile():
+def iiftests(c1: NumLike) -> list[NumLike]:
+    return [iif(c1 > 5, 8, 9),
+            iif(c1 < 5, 8.5, 9.5),
+            iif(1 > 5, 3.3, 8.8) + c1,
+            iif(1 < 5, c1 * 3.3, 8.8),
+            iif(c1 < 5, c1 * 3.3, 8.8)]
 
+
+def test_compile():
     c_i = cpvalue(9)
     c_f = cpvalue(1.111)
     c_b = cpvalue(True)
 
-    ret_test = function1(c_i) + function1(c_f) + function2(c_i) + function2(c_f) + function3(c_i) + function4(c_i) + function5(c_b) + [cpint(9) % 2]
-    ret_ref = function1(9) + function1(1.111) + function2(9) + function2(1.111) + function3(9) + function4(9) + function5(True) + [9 % 2]
+    ret_test = function1(c_i) + function1(c_f) + function2(c_i) + function2(c_f) + function3(c_i) + function4(c_i) + function5(c_b) + [cpint(9) % 2] + iiftests(c_i) + iiftests(c_f)
+    ret_ref = function1(9) + function1(1.111) + function2(9) + function2(1.111) + function3(9) + function4(9) + function5(True) + [9 % 2] + iiftests(9) + iiftests(1.111)
 
     tg = Target()
     print('* compile and copy ...')