buffers: allow sub operation.

* buf.c (sub_buf): New function.

* buf.h (sub_buf): Declared.

* lib.c (sub): Hook in BUF type.
(replace): Diagnose BUF specially as unsupported.

1 files changed, 1 insertions, 0 deletions

diff --git a/buf.h b/buf.h
index 60004112..db83f2a3 100644
--- a/buf.h
+++ b/buf.h
@@ -37,6 +37,7 @@ val length_buf(val buf);
 val buf_alloc_size(val buf);
 mem_t *buf_get(val buf, val self);
 void buf_fill(val buf, mem_t *src, val self);
+val sub_buf(val seq, val from, val to);
 
 #if HAVE_I8
 val buf_put_i8(val buf, val pos, val num);