[PATCH v1] rdelim: Add new procedure `for-line-in-file`.

From 3c7e1af1f4812d0e4c5d10e841cf9546e5ba2887 Mon Sep 17 00:00:00 2001
From: AwesomeAdam54321 <[email protected]>
Date: Sun, 15 Dec 2024 23:48:30 +0800
Subject: [PATCH v1] rdelim: Add new procedure `for-line-in-file`.

* module/ice-9/rdelim.scm (for-line-in-file): Add it.

This procedure makes it convenient to do per-line processing of a text
file.
---
 module/ice-9/rdelim.scm | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/module/ice-9/rdelim.scm b/module/ice-9/rdelim.scm
index d2cd081d7..833639219 100644
--- a/module/ice-9/rdelim.scm
+++ b/module/ice-9/rdelim.scm
@@ -23,7 +23,8 @@
 ;;; similar to (scsh rdelim) but somewhat incompatible.
 
 (define-module (ice-9 rdelim)
-  #:export (read-line
+  #:export (for-line-in-file
+            read-line
             read-line!
             read-delimited
             read-delimited!
@@ -206,3 +207,12 @@ characters to read.  By default, there is no limit."
 	      line)
       (else
        (error "unexpected handle-delim value: " handle-delim)))))
+
+(define (for-line-in-file file proc)
+  "Call PROC for every line in FILE until the eof-object is reached.
+The line provided to PROC is guaranteed to be a string."
+  (while #t
+    (let ((line (read-line file)))
+      (if (string? line)
+          (proc line)
+          (break)))))
-- 
2.41.0