From bb0de3e949440872576805fa06720b6e41f96220 Mon Sep 17 00:00:00 2001
From: Linus <bjornstam.linus@fastmail.se>
Date: Thu, 18 Feb 2021 22:06:59 +0100
Subject: [PATCH] Added some generator clauses

Now in-file, in-port, in-lists and in-generator have generator clauses
---
 goof.scm           |  2 +-
 goof/iterators.scm | 83 +++++++++++++++++++++++++++++++++++++---------
 2 files changed, 68 insertions(+), 17 deletions(-)

diff --git a/goof.scm b/goof.scm
index f1b22a9..dc2b660 100644
--- a/goof.scm
+++ b/goof.scm
@@ -33,7 +33,7 @@
   #:use-module (goof helpers)
   #:use-module (goof ref-let)
   #:use-module (rnrs io simple)
-  #:use-module ((srfi srfi-1) #:select (circular-list find))
+  #:use-module ((srfi srfi-1) #:select (any circular-list find))
   #:use-module ((srfi srfi-43) #:select (vector-copy vector-copy!))
   #:use-module (srfi srfi-71)
   #:use-module (ice-9 futures)
diff --git a/goof/iterators.scm b/goof/iterators.scm
index 9539f17..4fff15f 100644
--- a/goof/iterators.scm
+++ b/goof/iterators.scm
@@ -101,7 +101,23 @@
            ((elts (map car pairs))
             (succ (map step pairs)))
            ()
-           . rest))))
+           . rest))
+    ;; Generator clause
+    ((in-lists lists ...)
+     (gen-lists lists ...))))
+
+    
+;; TODO: make this not slow.
+(define (gen-lists . lists)
+  (lambda ()
+    (if (any null? lists)
+        (eof-object)
+        (let ((cars (map car lists))
+              (cdrs (map cdr lists)))
+          (set! lists cdrs)
+          (values cars)))))
+          
+  
 
 (define-syntax define-in-indexed
   (syntax-rules ()
@@ -156,22 +172,52 @@
            ((eof? var))
            ()
            ()
-           . rest))))
+           . rest))
+    ;; generator clauses
+    ((in-port port)
+     (gen-port port read-char eof-object?))
+    ((in-port port reader)
+     (gen-port port reader eof-object?))
+    ((in-port port reader eof?)
+     (gen-port port reader eof?))))
+
+(define (gen-port port read eof?)
+  (lambda ()
+    (let ((res (read port)))
+      (if (eof? res)
+          (eof-object)
+          res))))
 
 (define-syntax in-file
-(syntax-rules ()
-     ((in-file ((var) source) next . rest)
-      (in-file ((var p) source) next . rest))
-     ((in-file ((var p) (file)) next . rest)
-      (in-file ((var p) (file read-char)) next . rest))
-     ((in-file ((var p) (file reader)) next . rest)
-      (in-file ((var p) (file reader eof-object?)) next . rest))
-     ((in-file ((var p) (file reader eof?)) next . rest)
-      (next ((p (open-input-file file)) (r reader) (e? eof?))
-            ((var (r p) (r p)))
-            ((e? var))
-            ()
-            ((close-input-port p)) . rest))))
+  (syntax-rules ()
+    ((in-file ((var) source) next . rest)
+     (in-file ((var p) source) next . rest))
+    ((in-file ((var p) (file)) next . rest)
+     (in-file ((var p) (file read-char)) next . rest))
+    ((in-file ((var p) (file reader)) next . rest)
+     (in-file ((var p) (file reader eof-object?)) next . rest))
+    ((in-file ((var p) (file reader eof?)) next . rest)
+     (next ((p (open-input-file file)) (r reader) (e? eof?))
+           ((var (r p) (r p)))
+           ((e? var))
+           ()
+           ((close-input-port p)) . rest))
+    ;; generator clauses
+    ((in-file path)
+     (gen-file path read-char eof-object?))
+    ((in-file path read)
+     (gen-file path read eof-object?))
+    ((in-file path read eof?)
+     (gen-file path read eof?))))
+
+(define (gen-file path read eof?)
+  (let ((file (open-input-file path)))
+    (lambda ()
+      (let ((res (read file)))
+        (cond ((eof? res)
+               (close-port file)
+               (eof-object))
+              (else res))))))
 
 (define-syntax in-generator
   (syntax-rules ()
@@ -181,7 +227,12 @@
            ((eof-object? var))
            ()
            ()
-           . rest))))
+           . rest))
+    ;; yes, generator clause
+    ((in-generator gen)
+     (let ((g gen))
+       (lambda ()
+         (g))))))
 
 (define-syntax up-from
   (syntax-rules (to by)