slight comments cleanup

2 files changed, 14 insertions, 8 deletions

diff --git a/python/modules/cquoting.c b/python/modules/cquoting.c
index a929233d..2dcfc227 100644
--- a/python/modules/cquoting.c
+++ b/python/modules/cquoting.c
@@ -304,8 +304,12 @@ static PyObject *quote_bytea_raw(PyObject *self, PyObject *args)
 
 /* SQL unquote */
 static const char doc_unquote_literal[] =
-"Unquote SQL quoted string.\n\n"
-"C implementation.";
+"Unquote SQL value.\n\n"
+"E'..' -> extended quoting.\n"
+"'..' -> standard or extended quoting\n"
+"null -> None\n"
+"other -> returned as-is\n\n"
+"C implementation.\n";
 
 static PyObject *do_sql_ext(unsigned char *src, Py_ssize_t src_len)
 {
diff --git a/python/skytools/_pyquoting.py b/python/skytools/_pyquoting.py
index 1b143953..32d548ff 100644
--- a/python/skytools/_pyquoting.py
+++ b/python/skytools/_pyquoting.py
@@ -20,8 +20,9 @@ __all__ = [
 def quote_literal(s):
     """Quote a literal value for SQL.
 
-    If string contains '\\', it is quoted and result is prefixed with E.
-    Input value of None results in string "null" without quotes.
+    If string contains '\\', extended E'' quoting is used,
+    otherwise standard quoting.  Input value of None results
+    in string "null" without quotes.
 
     Python implementation.
     """
@@ -69,8 +70,6 @@ def quote_bytea_raw(s):
             else:
                 _bytea_map[c] = c
     return "".join([_bytea_map[c] for c in s])
-    # faster but does not match c code
-    #return s.replace("\\", "\\\\").replace("\0", "\\000")
 
 #
 # Database specific urlencode and urldecode.
@@ -167,8 +166,11 @@ def _sub_unescape_sqlext(m):
 
 def unquote_literal(val, stdstr = False):
     """Unquotes SQL string.
-    Ordinary '' quoted string can be both standard and extended quoted.
-    E'' quoting is always taken as extended quoted.
+
+    E'..' -> extended quoting.
+    '..' -> standard or extended quoting
+    null -> None
+    other -> returned as-is
     """
     if val[0] == "'" and val[-1] == "'":
         if stdstr: