sim and deploy should work on Snow Leopard

bin/sim.m

@@ -131,6 +131,37 @@ current_repl_prompt(id delegate, NSString *top_level)
 	   top_level, question];
 }
 
+#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
+// This readline function is not implemented in Snow Leopard.
+// Code copied from http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libedit/readline.c?only_with_tag=MAIN
+#if !defined(RL_PROMPT_START_IGNORE)
+# define RL_PROMPT_START_IGNORE  '\1'
+#endif
+#if !defined(RL_PROMPT_END_IGNORE)
+# define RL_PROMPT_END_IGNORE    '\2'
+#endif
+int
+rl_set_prompt(const char *prompt)
+{
+    char *p;
+
+    if (!prompt)
+	prompt = "";
+    if (rl_prompt != NULL && strcmp(rl_prompt, prompt) == 0) 
+	return 0;
+    if (rl_prompt)
+	/*el_*/free(rl_prompt);
+    rl_prompt = strdup(prompt);
+    if (rl_prompt == NULL)
+	return -1;
+
+    while ((p = strchr(rl_prompt, RL_PROMPT_END_IGNORE)) != NULL)
+	*p = RL_PROMPT_START_IGNORE;
+
+    return 0;
+}
+#endif
+
 static void
 refresh_repl_prompt(id delegate, NSString *top_level, bool clear)
 {