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+import Lean
+import Lean.Meta.Tactic.Simp
+import Mathlib.Tactic.Linarith
+import Base.Primitives.Scalar
+import Base.Arith
+
+namespace Primitives
+
+open Lean Meta Elab Term
+
+/- Something strange happens here: when we solve the goal with scalar_tac, it
+   sometimes leaves meta-variables in place, which then causes issues when
+   type-checking functions. For instance, it happens when we have const-generics
+   in the translation: the constants contain meta-variables, which are then
+   used in the types, which cause issues later. An example is given below:
+ -/
+macro:max x:term:max noWs "#isize" : term => `(Isize.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#i8"    : term => `(I8.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#i16"   : term => `(I16.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#i32"   : term => `(I32.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#i64"   : term => `(I64.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#i128"  : term => `(I128.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#usize" : term => `(Usize.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#u8"    : term => `(U8.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#u16"   : term => `(U16.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#u32"   : term => `(U32.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#u64"   : term => `(U64.ofInt $x (by first | decide | scalar_tac))
+macro:max x:term:max noWs "#u128"  : term => `(U128.ofInt $x (by first | decide | scalar_tac))
+
+-- Notation for pattern matching
+-- We make the precedence looser than the negation.
+notation:70 a:70 "#scalar" => Scalar.mk (a) _ _
+
+/- Testing the notations -/
+example := 0#u32
+example := 1#u32
+example := 1#i32
+example := 0#isize
+example := (-1)#isize
+
+example := 1#u32
+
+/-
+-- This doesn't work anymore
+example (x : U32) : Bool :=
+  match x with
+  | 0#u32 => true
+  | _ => false
+
+example (x : U32) : Bool :=
+  match x with
+  | 1#u32 => true
+  | _ => false
+
+example (x : I32) : Bool :=
+  match x with
+  | (-1)#i32 => true
+  | _ => false
+-/
+
+example (x : U32) : Bool :=
+  match x with
+  | 0#scalar => true
+  | _ => false
+
+example (x : U32) : Bool :=
+  match x with
+  | 1#scalar => true
+  | _ => false
+
+example (x : I32) : Bool :=
+  match x with
+  | (-1)#scalar => true
+  | _ => false
+
+example {ty} (x : Scalar ty) : ℤ :=
+  match x with
+  | v#scalar => v
+
+example {ty} (x : Scalar ty) : Bool :=
+  match x with
+  | 1#scalar => true
+  | _ => false
+
+example {ty} (x : Scalar ty) : Bool :=
+  match x with
+  | -(1 : Int)#scalar => true
+  | _ => false
+
+-- Testing the notations
+example : Result Usize := 0#usize + 1#usize
+
+-- More complex expressions
+example (x y : Int) (h : 0 ≤ x + y ∧ x + y ≤ 1000) : U32 := (x + y)#u32
+
+namespace Scalar.Examples
+
+  abbrev Array (a : Type) (len : U32) := { l : List a // l.length = len.val }
+
+  -- Checking the syntax
+  example : Array Int 0#u32 := ⟨ [], by simp ⟩
+
+  /- The example below fails if we don't use `decide` in the elaboration
+     of the scalar notation -/
+  example (a : Array (Array Int 32#u32) 32#u32) := a
+
+end Scalar.Examples
+
+end Primitives