Switch to nix provided exercism

Nixpkgs already provides exercism in latest version
Add one on top level to get started with new languages.

c/shell.nix

@@ -6,6 +6,6 @@ pkgs.mkShellNoCC {
   name = "exercism";
   buildInputs = [
     pkgs.coreutils
-    (pkgs.callPackage ../exercism.nix { })
+    pkgs.exercism
   ];
 }

exercism.nix

@@ -1,25 +0,0 @@
-{
-  buildGoModule
-  , fetchFromGitHub
-  , lib
-}:
-
-buildGoModule rec {
-  pname = "exercism";
-  version = "3.3.0";
-  src = fetchFromGitHub {
-    owner = "exercism";
-    repo = "cli";
-    rev = "v${version}";
-    sha256 = "Mtb5c1/k8kp7bETOSE0X969BV176jpoprr1/mQ3E4Vg=";
-  };
-
-  vendorHash = "sha256-fnsSvbuVGRAndU88su2Ck7mV8QBDhxozdmwI3XGtxcA=";
-
-  meta = with lib; {
-    homepage = "https://github.com/exercism/cli";
-    description = "Command line interface for exercism website";
-    license = licenses.mit;
-    platforms = platforms.linux;
-  };
-}

go/shell.nix

@@ -6,6 +6,6 @@ pkgs.mkShellNoCC {
   name = "exercism";
   buildInputs = [
     pkgs.go
-    (pkgs.callPackage ../exercism.nix { })
+    pkgs.exercism
   ];
 }

lua/shell.nix

@@ -6,6 +6,6 @@ pkgs.mkShellNoCC {
   name = "exercism";
   buildInputs = [
     (pkgs.lua.withPackages(ps: with ps; [ busted]))
-    (pkgs.callPackage ../exercism.nix { })
+    pkgs.exercism
   ];
 }

python/shell.nix

@@ -6,6 +6,6 @@ pkgs.mkShellNoCC {
   name = "exercism";
   buildInputs = [
     (pkgs.python311.withPackages(ps: with ps; [ pytest ]))
-    (pkgs.callPackage ../exercism.nix { })
+    pkgs.exercism
   ];
 }

python/triangle/triangle.py

@@ -1,10 +1,29 @@
-def equilateral(sides):
-    pass
+def is_triangle(sides):
+    for side in sides:
+        if side <= 0:
+            return False
 
+    if sides[0] + sides[1] >= sides[2]:
+        return True
+    if sides[1] + sides[2] >= sides[0]:
+        return True
+    if sides[0] + sides[2] >= sides[1]:
+        return True
+
+def equilateral(sides):
+    if not is_triangle(sides):
+        return False
+
+    return sides[0] == sides[1] == sides[2]
 
 def isosceles(sides):
-    pass
+    if not is_triangle(sides):
+        return false
 
+    return sides[0] == sides[1] or sides[0] == sides[2] or sides[1] == sides[2]
 
 def scalene(sides):
-    pass
+    if not is_triangle(sides):
+        return false
+
+    return sides[0] != sides[1] and sides[0] != sides[2] and sides[1] != sides[2]

rust/shell.nix

@@ -9,6 +9,6 @@ pkgs.mkShellNoCC {
     pkgs.rustc
     pkgs.cargo
 
-    (pkgs.callPackage ../exercism.nix { })
+    pkgs.exercism
   ];
 }

shell.nix

@@ -0,0 +1,10 @@
+{
+  pkgs ? import <nixpkgs> { }
+}:
+
+pkgs.mkShellNoCC {
+  name = "exercism";
+  buildInputs = [
+    pkgs.exercism
+  ];
+}