Merge pull request #1157 from zevv/file-lines

Add file/lines iterator

src/boot/boot.janet

@@ -1746,6 +1746,14 @@
   (printf (dyn *pretty-format* "%q") x)
   (flush))
 
+
+(defn file/lines
+  "Return an iterator over the lines of a file."
+  [file]
+  (coro
+    (while (def line (file/read file :line))
+      (yield line))))
+
 ###
 ###
 ### Pattern Matching

test/suite0009.janet

@@ -102,6 +102,20 @@
     (os/execute [janet "-e" `(repeat 20 (print :hello))`] :p {:out f})
     (file/flush f)))
 
+# each-line iterator
+
+(assert-no-error "file/lines iterator"
+   (def outstream (os/open "unique.txt" :wct))
+   (def buf1 "123\n456\n")
+   (defer (:close outstream)
+     (:write outstream buf1))
+   (var buf2 "")
+   (with [f (file/open "unique.txt" :r)]
+     (each line (file/lines f)
+        (set buf2 (string buf2 line))))
+   (assert (= buf1 buf2) "file/lines iterator")
+   (os/rm "unique.txt"))
+
 # Issue #593
 (assert-no-error "file writing 3"
   (def outfile (file/open "unique.txt" :w))