Jürgen,
I submitted this patch in a slightly different form once before; it
didn't make it into GNU APL.
After having lived with the patch for a while on my own system, I've
updated it to the current form.
The gist of the patch is to acknowledge redefinition of a ]usercmd with
*identical* arguments as being successful rather than complaining about
a "BAD COMMAND". The patch does not change the effect of the command,
only the report.
With the patch, GNU APL will report
"User-defined command ]... installed"
each time a command is defined with identical arguments.
I think this is a better response than complaining
"BAD COMMAND"
in the same circumstance, given that the behavior actually succeeded.
I hope that you'll apply this patch to GNU APL.
Best wishes,
David
Index: src/Command.cc
===================================================================
--- src/Command.cc (revision 294)
+++ src/Command.cc (working copy)
@@ -837,6 +837,33 @@
return true;
}
//-----------------------------------------------------------------------------
+bool
+Command::check_redefinition(ostream & out, const UCS_string & cnew,
+ const UCS_string fnew, const int mnew)
+{
+ loop(u, user_commands.size())
+ {
+ const UCS_string cold = user_commands[u].prefix;
+ const UCS_string fold = user_commands[u].apl_function;
+ const int mold = user_commands[u].mode;
+
+ if (cnew != cold) continue;
+
+ // user command name matches; so must mode and function
+ if (mnew != mold || fnew != fold)
+ {
+ out << "BAD COMMAND" << endl;
+ Workspace::more_error()
+ = UCS_string(
+ "conflict with existing user command definition"
+ " in command ]USERCMD");
+ }
+ return true;
+ }
+
+ return false;
+}
+//-----------------------------------------------------------------------------
void
Command::cmd_USERCMD(ostream & out, const UCS_string & cmd,
vector<UCS_string> & args)
@@ -922,8 +949,12 @@
#define cmd_def(cmd_str, _cod, arg) \
if (check_name_conflict(out, cmd_str, args[0])) return;
#include "Command.def"
- loop(u, user_commands.size())
- if (check_name_conflict(out, args[0], user_commands[u].prefix)) return;
+ if (check_redefinition(out, args[0], args[1], mode))
+ {
+ out << " User-defined command "
+ << args[0] << " installed." << endl;
+ return;
+ }
// check APL function name
//
Index: src/Command.hh
===================================================================
--- src/Command.hh (revision 294)
+++ src/Command.hh (working copy)
@@ -121,6 +121,9 @@
static bool check_name_conflict(ostream & out, const UCS_string & cnew,
const UCS_string cold);
+ static bool check_redefinition(ostream & out, const UCS_string & cnew,
+ const UCS_string fnew, const int mnew);
+
/// a helper struct for the )IN command
struct transfer_context
{
