diff --git a/complete.cpp b/complete.cpp
index b75b940a1..2e0894b63 100644
--- a/complete.cpp
+++ b/complete.cpp
@@ -907,15 +907,11 @@ static void complete_strings( std::vector<completion_t> &comp_out,
 							  std::vector<completion_t> &possible_comp,
 							  int flags )
 {
-	wchar_t *wc, *tmp;
-
-	tmp = expand_one( 0,
-					  wcsdup(wc_escaped), EXPAND_SKIP_CMDSUBST | EXPAND_SKIP_WILDCARDS);
-	if(!tmp)
-		return;
-
-	wc = parse_util_unescape_wildcards( tmp );
-	free(tmp);
+    wcstring tmp = wc_escaped;
+    if (! expand_one(tmp, EXPAND_SKIP_CMDSUBST | EXPAND_SKIP_WILDCARDS))
+        return;
+    
+	const wchar_t *wc = parse_util_unescape_wildcards( tmp.c_str() );
 	
 	for( size_t i=0; i< possible_comp.size(); i++ )
 	{
@@ -928,7 +924,7 @@ static void complete_strings( std::vector<completion_t> &comp_out,
 		}
 	}
 
-	free( wc );
+	free( (void *)wc );
 }
 
 /**
diff --git a/expand.cpp b/expand.cpp
index cd678d8af..b0fbcf97a 100644
--- a/expand.cpp
+++ b/expand.cpp
@@ -2585,7 +2585,7 @@ int expand_string( void *context,
 }
 */
 
-wchar_t *expand_one( void *context, wchar_t *string, int flags )
+wchar_t *expand_one( void *context, const wchar_t *string, int flags )
 {
 	std::vector<completion_t> l;
 	int res;
@@ -2595,8 +2595,8 @@ wchar_t *expand_one( void *context, wchar_t *string, int flags )
 	
 	if( (!(flags & ACCEPT_INCOMPLETE)) &&  expand_is_clean( string ) )
 	{
-		halloc_register( context, string );
-		return string;
+		halloc_register( context, (void *)string );
+		return (wchar_t *)string;
 	}
 	
 //	al_init( &l );
@@ -2625,5 +2625,17 @@ wchar_t *expand_one( void *context, wchar_t *string, int flags )
         halloc_register( context, one );
 	return one;
 }
+
+bool expand_one( wcstring &in, int flag ) {
+    bool result = false;
+    wchar_t *res = expand_one(NULL, in.c_str(), flag);
+    if (res) {
+        in = res;
+        free(res);
+        result = true;
+    }
+    return result;
+}
+
  
 
diff --git a/expand.h b/expand.h
index 0d235ea55..255b985bc 100644
--- a/expand.h
+++ b/expand.h
@@ -165,7 +165,10 @@ __warn_unused int expand_string2( const wcstring &input, std::vector<completion_
    \param flag Specifies if any expansion pass should be skipped. Legal values are any combination of EXPAND_SKIP_CMDSUBST EXPAND_SKIP_VARIABLES and EXPAND_SKIP_WILDCARDS
    \return The expanded parameter, or 0 on failiure
 */
-wchar_t *expand_one( void *context, wchar_t *in, int flag );
+wchar_t *expand_one( void *context, const wchar_t *in, int flag );
+
+/** expand_one for a wcstring. Modifies the string in-place, returning true on success and false on failure */
+bool expand_one( wcstring &inout_str, int flag );
 
 /**
    Convert the variable value to a human readable form, i.e. escape things, handle arrays, etc. Suitable for pretty-printing. The result must be free'd!
diff --git a/highlight.cpp b/highlight.cpp
index f0fbacea1..8f7cbf884 100644
--- a/highlight.cpp
+++ b/highlight.cpp
@@ -605,11 +605,10 @@ void tokenize( const wchar_t * const buff, int * const color, const int pos, arr
 					
 					if( cmd && (wcscmp( cmd, L"cd" ) == 0) )
 					{
-						wchar_t *dir = expand_one( context, 
-												  wcsdup(tok_last( &tok )),
-												  EXPAND_SKIP_CMDSUBST );
-						if( dir )
+                        wcstring dir_str = tok_last( &tok );
+                        if (expand_one(dir_str, EXPAND_SKIP_CMDSUBST))
 						{
+                            const wchar_t *dir = dir_str.c_str();
 							int is_long_help = wcsncmp(dir,L"--help", wcslen(dir) );
 							int is_short_help = wcsncmp(dir,L"-h", wcslen(dir) );
 							
diff --git a/parser.cpp b/parser.cpp
index f1c803174..f2a52e3a4 100644
--- a/parser.cpp
+++ b/parser.cpp
@@ -1969,7 +1969,7 @@ int parser_t::parse_job( process_t *p,
 						*/
 						if( wcschr( cmd, L'=' ) )
 						{
-							wchar_t *cpy = halloc_wcsdup( j, cmd );
+							wchar_t *cpy = wcsdup( cmd );
 							wchar_t *valpart = wcschr( cpy, L'=' );
 							*valpart++=0;
 							
@@ -1978,6 +1978,7 @@ int parser_t::parse_job( process_t *p,
 								   cmd,
 								   cpy,
 								   valpart);
+							free(cpy);
 							
 						}
 						else if(cmd[0]==L'$')
@@ -2112,9 +2113,7 @@ int parser_t::parse_job( process_t *p,
 			{
 			
 				int end_pos = end-tok_string( tok );
-				wchar_t *sub_block= halloc_wcsndup( j,
-													tok_string( tok ) + current_tokenizer_pos,
-													end_pos - current_tokenizer_pos);
+                const wcstring sub_block(tok_string( tok ) + current_tokenizer_pos, end_pos - current_tokenizer_pos);
 			
 				p->type = INTERNAL_BLOCK;
 				completion_t data_to_push;