From 010b584ef1504d85bb2e9cddf0d37ad21b15bb6e Mon Sep 17 00:00:00 2001
From: Scott Richmond <kredati@users.noreply.github.com>
Date: Sun, 19 May 2024 19:35:41 -0400
Subject: [PATCH] partial function application!

---
 janet/interpreter.janet | 46 ++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 14 deletions(-)

diff --git a/janet/interpreter.janet b/janet/interpreter.janet
index 40ef568..bd761ea 100644
--- a/janet/interpreter.janet
+++ b/janet/interpreter.janet
@@ -11,8 +11,8 @@
 (defn- todo [msg] (error (string "not yet implemented: " msg)))
 
 (defn- resolve-name [name ctx]
-  (print "resolving " name " in:")
-  (pp ctx)
+  # (print "resolving " name " in:")
+  # (pp ctx)
   (when (not ctx) (break :^not-found))
   (if (has-key? ctx name)
     (ctx name)
@@ -20,7 +20,7 @@
 
 (defn- match-word [word value ctx]
   (def name (word :data))
-  (print "matched " (b/show value) " to " name)
+  # (print "matched " (b/show value) " to " name)
   (set (ctx name) value)
   {:success true :ctx ctx})
 
@@ -321,14 +321,30 @@
   (set (ctx name) the-fn))
 
 # TODO
-(defn- partial [the-fn args] (todo "partially applied functions"))
+(defn- is_placeholder [x] (= x :_))
 
-(defn- call-fn [the-fn args]
+(var call-fn nil)
+
+(defn- partial [the-fn partial-args] 
+  (print "calling partially applied function")
+  (def args (partial-args :args))
+  (def pos (find-index is_placeholder args))
+  (def name (string (the-fn :name) "<partial>"))
+  (fn [missing]
+    (print "calling function with arg " (b/show missing))
+    (pp partial-args)
+    (def full-args (array/slice args))
+    (set (full-args pos) missing)
+    (print "all args: " (b/show full-args))
+    (call-fn the-fn [;full-args])))
+
+(defn- call-fn* [the-fn args]
   (print "calling " (b/show the-fn))
   (print "with args " (b/show args))
   (when (or 
     (= :function (type the-fn)) 
     (= :cfunction (type the-fn))) 
+      (print "Janet function")
       (break (the-fn ;args)))
   (def clauses (the-fn :body))
   (def len (length clauses))
@@ -353,11 +369,11 @@
   (set (the-fn :match) match-fn)
   (match-fn 0 args))
 
+(set call-fn call-fn*)
+
 (defn- apply-synth-term [prev curr]
-  (print "applying")
-  (pp curr)
-  (print "to")
-  (pp prev)
+  (print "applying " (b/show prev))
+  (print "to" (b/show curr))
   (def types [(b/ludus/type prev) (b/ludus/type curr)])
   (print "typle:")
   (pp types)
@@ -406,9 +422,7 @@
 
 (defn- recur [ast ctx] (todo "recur"))
 
-(defn- repeatt [ast ctx] (todo "repeat"))
-
-(defn - testt [ast ctx] (todo "test"))
+(defn- testt [ast ctx] (todo "test"))
 
 (defn- interpret* [ast ctx]
   (print "interpreting node " (ast :type))
@@ -494,9 +508,13 @@
 
 (do 
 (set source `
-
+fn foobar {
+  (:foo, :bar) -> :foobar!
+  (_, _) -> :not_foobar
+}
+let bar = foobar (:foo, _)
+bar (:baz)
 `)
 (def result (run))
-(b/show result)
 )