From 851267692232e8469c51bc04d51b7c8a2548b2e5 Mon Sep 17 00:00:00 2001
From: Tommi Reiman <tommi@iki.fi>
Date: Fri, 28 Oct 2022 17:01:05 +0300
Subject: [PATCH] mx/def

---
 .../metosin/malli/config.edn                  |  3 +-
 src/demo.clj                                  | 26 +++++++++++
 src/malli/experimental.cljc                   | 43 ++++++++++++++++---
 3 files changed, 66 insertions(+), 6 deletions(-)
 create mode 100644 src/demo.clj

diff --git a/resources/clj-kondo/clj-kondo.exports/metosin/malli/config.edn b/resources/clj-kondo/clj-kondo.exports/metosin/malli/config.edn
index 0f8b25ccf..d322f5243 100644
--- a/resources/clj-kondo/clj-kondo.exports/metosin/malli/config.edn
+++ b/resources/clj-kondo/clj-kondo.exports/metosin/malli/config.edn
@@ -1,2 +1,3 @@
-{:lint-as {malli.experimental/defn schema.core/defn}
+{:lint-as {malli.experimental/defn schema.core/defn
+           malli.experimental/def schema.core/def}
  :linters {:unresolved-symbol {:exclude [(malli.core/=>)]}}}
diff --git a/src/demo.clj b/src/demo.clj
new file mode 100644
index 000000000..618242b15
--- /dev/null
+++ b/src/demo.clj
@@ -0,0 +1,26 @@
+(ns demo
+  (:require [malli.experimental :as mx]
+            [malli.provider :as mp]))
+
+;; pull schema from example
+(def Config
+  (mp/provide
+   [{:port 8080
+     :host "127.0.0.1"
+     :db {:adapter "postgresql"
+          :username "example"
+          :password "example"
+          :server-name "localhost"
+          :port-number 5432
+          :database-name "example"}}]))
+
+;; fail fast
+(mx/def config :- Config
+  {:port "8080"
+   :host "127.0.0.1"
+   :db {:adapter "postgresql"
+        :username "example"
+        :password "example"
+        :server-name "localhost"
+        :port-number "5432"
+        :database-name :example}})
diff --git a/src/malli/experimental.cljc b/src/malli/experimental.cljc
index dbf7f137c..5727eefb9 100644
--- a/src/malli/experimental.cljc
+++ b/src/malli/experimental.cljc
@@ -3,9 +3,10 @@
   #?(:cljs (:require-macros malli.experimental))
   (:require [clojure.core :as c]
             [malli.core :as m]
-            [malli.destructure :as md]))
+            [malli.destructure :as md]
+            [malli.dev.pretty :as pretty]))
 
-(c/defn -schema [inline-schemas]
+(c/defn -defn-schema [inline-schemas]
   (m/schema
    [:schema
     {:registry {"Schema" any?
@@ -32,8 +33,28 @@
                                                  [:meta [:? :map]]]]]]]}}
     "Params"]))
 
-(def SchematizedParams (-schema true))
-(def Params (-schema false))
+(c/defn -def-schema [inline-schemas]
+  (m/schema
+   [:schema
+    {:registry {"Schema" any?
+                "Separator" (if inline-schemas [:= :-] md/Never)
+                "Params" [:catn
+                          [:name symbol?]
+                          [:return [:? [:catn
+                                        [:- "Separator"]
+                                        [:schema "Schema"]]]]
+                          [:doc [:? string?]]
+                          [:body any?]]}}
+    "Params"]))
+
+(def SchematizedDefnParams (-defn-schema true))
+(def DefnParams (-defn-schema false))
+
+(def ^:depecated SchematizedParams SchematizedDefnParams)
+(def ^:depecated Params DefnParams)
+
+(def SchematizedDefParams (-def-schema true))
+(def DefParams (-def-schema false))
 
 (c/defn -defn [schema args]
   (let [{:keys [name return doc arities] body-meta :meta :as parsed} (m/parse schema args)
@@ -64,8 +85,20 @@
        (m/=> ~name ~schema)
        defn#)))
 
+(c/defn -def [schema args]
+  (let [{:keys [name doc body] {:keys [schema]} :return :as parsed} (m/parse schema args)]
+    (when (= ::m/invalid parsed) (m/-fail! ::parse-error {:schema schema, :args args}))
+    `(let [def# (def
+                  ~(with-meta name {:schema schema})
+                  ~@(some-> doc vector))]
+       (when (and ~schema (not (m/validate ~schema ~body)))
+         (pretty/explain ~schema ~body)
+         (m/-fail! ::invalid-data {:def ~name, :schema ~schema, :body ~body}))
+       def#)))
+
 ;;
 ;; public api
 ;;
 
-#?(:clj (defmacro defn [& args] (-defn SchematizedParams args)))
+#?(:clj (defmacro defn [& args] (-defn SchematizedDefnParams args)))
+#?(:clj (defmacro def [& args] (-def SchematizedDefParams args)))