From 7e5ea5e41432e719ab7b9ef8d408a8a91036d5e2 Mon Sep 17 00:00:00 2001
From: LordBaryhobal <lordbaryhobal@gmail.com>
Date: Mon, 22 Jun 2026 15:29:39 +0200
Subject: [PATCH] chore: add example to demonstrate some features

---
 examples/02_demonstration/demo.midas | 10 ++++++++++
 examples/02_demonstration/demo.py    | 19 +++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 examples/02_demonstration/demo.midas
 create mode 100644 examples/02_demonstration/demo.py

diff --git a/examples/02_demonstration/demo.midas b/examples/02_demonstration/demo.midas
new file mode 100644
index 0000000..394cc15
--- /dev/null
+++ b/examples/02_demonstration/demo.midas
@@ -0,0 +1,10 @@
+predicate in_range(min: float, max: float)(v: float) = min <= v & v <= max
+predicate is_ratio = in_range(0, 1)
+
+type Money = float
+type Price[T <: Money] = T where _ >= 0
+
+type EUR = Money
+type USD = Money
+
+type Reduction = float where is_ratio(_)
diff --git a/examples/02_demonstration/demo.py b/examples/02_demonstration/demo.py
new file mode 100644
index 0000000..20e5bb5
--- /dev/null
+++ b/examples/02_demonstration/demo.py
@@ -0,0 +1,19 @@
+from typing import TypeVar, cast
+
+from demo_stubs import EUR, USD, Money, Price, Reduction
+
+T = TypeVar("T", bound=Money)
+
+
+def apply_reduction(amount: Price[T], reduction: Reduction) -> Price[T]:
+    return cast(Price[T], (1.0 - reduction) * amount)
+
+
+a1 = cast(Price[EUR], 3.2)
+a2 = cast(Price[USD], 10.4)
+r1: Reduction = cast(Reduction, 0.2)
+
+print(apply_reduction(a1, r1))
+print(apply_reduction(a2, r1))
+
+# a3 = a1 + a2