Semantics change in trim-str function.

* lib.c (trim_str): Trim only newlines and blanks,
not carriage returns, vertical tabs and form feeds.
This is subject to the compatibility option

* txr.1: Doc updated and compatibility note
added.

2 files changed, 18 insertions, 7 deletions

diff --git a/lib.c b/lib.c
index 61a43c01..5ca640c5 100644
--- a/lib.c
+++ b/lib.c
@@ -3916,11 +3916,19 @@ val trim_str(val str)
   const wchar_t *start = c_str(str);
   const wchar_t *end = start + c_num(length_str(str));
 
-  while (start[0] && iswspace(start[0]))
-    start++;
+  if (opt_compat && opt_compat <= 148) {
+    while (start[0] && iswspace(start[0]))
+      start++;
 
-  while (end > start && iswspace(end[-1]))
-    end--;
+    while (end > start && iswspace(end[-1]))
+      end--;
+  } else {
+    while (start[0] && wcschr(L" \t\n", start[0]))
+      start++;
+
+    while (end > start && wcschr(L" \t\n", end[-1]))
+      end--;
+  }
 
   if (end == start) {
     return null_string;
diff --git a/txr.1 b/txr.1
index f2e2539e..23c7bc1f 100644
--- a/txr.1
+++ b/txr.1
@@ -18632,8 +18632,7 @@ The
 function produces a copy of
 .meta string
 from which leading and
-trailing whitespace is removed. Whitespace consists of spaces, tabs,
-carriage returns, linefeeds, vertical tabs and form feeds.
+trailing tabs, spaces and newlines are removed.
 
 .coNP Function @ chrp
 .synb
@@ -44798,7 +44797,11 @@ were executed in derived-to-base order, opposite to the
 order of execution of
 .code :init
 handlers. Specifying 148 or earlier compatibility provides this
-old behavior.
+old behavior. Also, until version 148, the
+.code trim-str
+function stripped leading and trailing whitespace from a string
+consisting of not only spaces, tabs and newlines, but also carriage
+returns, vertical tabs and form feeds.
 .IP 145
 In versions 144 and 145, \*(TX opened files in text mode on Cygwin,
 enabling conversion between CR-LF line endings and abstract newline