Treat comment lines in repl, and plug memory leak.

* parser.c (repl): If we continue the loop due to detecting a
blank line, we must free that line, since we are outside of
the unwind block (and continue would violate that block if we
were). If a line contains nothing but a comment, then enter
that line into the history.

* txr.1: Documented treatment of commented lines.

2 files changed, 24 insertions, 4 deletions

diff --git a/parser.c b/parser.c
index 48449dc8..8719b03d 100644
--- a/parser.c
+++ b/parser.c
@@ -581,8 +581,20 @@ val repl(val bindings, val in_stream, val out_stream)
       break;
     }
 
-    if (strspn(line_u8, " \t") == strlen(line_u8))
-      continue;
+    {
+      size_t wsp = strspn(line_u8, " \t\n\r");
+
+      if (line_u8[wsp] == 0) {
+        free(line_u8);
+        continue;
+      }
+
+      if (line_u8[wsp] == ';') {
+        lino_hist_add(ls, line_u8);
+        free(line_u8);
+        continue;
+      }
+    }
 
     counter = succ(counter);
 
diff --git a/txr.1 b/txr.1
index 32799345..5e054e83 100644
--- a/txr.1
+++ b/txr.1
@@ -33259,8 +33259,16 @@ intercepts the exception and prints information about it preceded by
 two asterisks and a space. These asterisks distinguish an exception from a
 result value.
 
-If an empty line is entered, or a line containing only spaces and tabs,
-the prompt is repeated without incrementing the number.
+If an empty line is entered, or a line containing only spaces, tabs
+or embedded carriage returns or linefeeds, the prompt is repeated without
+incrementing the number. Such a line is not entered into the history.
+
+A line which only contains a \*(TL comment (optional spaces, tabs or embedded
+carriage returns or linefeeds, followed by a semicolon), also causes
+the prompt to be repeated without incrementing the number. However,
+such a line
+.B is
+entered into the history.
 
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