updated for version 7.0001v7.0001

1 files changed, 2004 insertions, 0 deletions

diff --git a/src/ex_eval.c b/src/ex_eval.c
new file mode 100644
index 0000000000..921d608670
--- /dev/null
+++ b/src/ex_eval.c
@@ -0,0 +1,2004 @@
+/* vi:set ts=8 sts=4 sw=4:
+ *
+ * VIM - Vi IMproved	by Bram Moolenaar
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+
+/*
+ * ex_eval.c: functions for Ex command line for the +eval feature.
+ */
+
+#include "vim.h"
+
+#if defined(FEAT_EVAL) || defined(PROTO)
+
+static void	free_msglist __ARGS((struct msglist *l));
+static int	throw_exception __ARGS((void *, int, char_u *));
+static void	rewind_conditionals __ARGS((struct condstack *,
+							    int, int, int *));
+
+/*
+ * Exception handling terms:
+ *
+ *	:try		":try" command		\
+ *	    ...		try block		|
+ *	:catch RE	":catch" command	|
+ *	    ...		catch clause		|- try conditional
+ *	:finally	":finally" command	|
+ *	    ...		finally clause		|
+ *	:endtry		":endtry" command	/
+ *
+ * The try conditional may have any number of catch clauses and at most one
+ * finally clause.  A ":throw" command can be inside the try block, a catch
+ * clause, the finally clause, or in a function called or script sourced from
+ * there or even outside the try conditional.  Try conditionals may be nested.
+ */
+
+/*
+ * Configuration whether an exception is thrown on error or interrupt.  When
+ * the preprocessor macros below evaluate to FALSE, an error (did_emsg) or
+ * interrupt (got_int) under an active try conditional terminates the script
+ * after the non-active finally clauses of all active try conditionals have been
+ * executed.  Otherwise, errors and/or interrupts are converted into catchable
+ * exceptions (did_throw additionally set), which terminate the script only if
+ * not caught.  For user exceptions, only did_throw is set.  (Note: got_int can
+ * be set asyncronously afterwards by a SIGINT, so did_throw && got_int is not
+ * a reliant test that the exception currently being thrown is an interrupt
+ * exception.  Similarly, did_emsg can be set afterwards on an error in an
+ * (unskipped) conditional command inside an inactive conditional, so did_throw
+ * && did_emsg is not a reliant test that the exception currently being thrown
+ * is an error exception.)  -  The macros can be defined as expressions checking
+ * for a variable that is allowed to be changed during execution of a script.
+ */
+#if 0
+/* Expressions used for testing during the development phase. */
+# define THROW_ON_ERROR		(!eval_to_number("$VIMNOERRTHROW"))
+# define THROW_ON_INTERRUPT	(!eval_to_number("$VIMNOINTTHROW"))
+# define THROW_TEST
+#else
+/* Values used for the Vim release. */
+# define THROW_ON_ERROR		TRUE
+# define THROW_ON_INTERRUPT	TRUE
+#endif
+
+static void	catch_exception __ARGS((except_T *excp));
+static void	finish_exception __ARGS((except_T *excp));
+static void	discard_exception __ARGS((except_T *excp, int was_finished));
+static void	report_pending __ARGS((int action, int pending, void *value));
+
+/*
+ * When several errors appear in a row, setting "force_abort" is delayed until
+ * the failing command returned.  "cause_abort" is set to TRUE meanwhile, in
+ * order to indicate that situation.  This is useful when "force_abort" was set
+ * during execution of a function call from an expression: the aborting of the
+ * expression evaluation is done without producing any error messages, but all
+ * error messages on parsing errors during the expression evaluation are given
+ * (even if a try conditional is active).
+ */
+static int cause_abort = FALSE;
+
+/*
+ * Return TRUE when immdediately aborting on error, or when an interrupt
+ * occurred or an exception was thrown but not caught.  Use for ":{range}call"
+ * to check whether an aborted function that does not handle a range itself
+ * should be called again for the next line in the range.  Also used for
+ * cancelling expression evaluation after a function call caused an immediate
+ * abort.  Note that the first emsg() call temporarily resets "force_abort"
+ * until the throw point for error messages has been reached.  That is, during
+ * cancellation of an expression evaluation after an aborting function call or
+ * due to a parsing error, aborting() always returns the same value.
+ */
+    int
+aborting()
+{
+    return (did_emsg && force_abort) || got_int || did_throw;
+}
+
+/*
+ * The value of "force_abort" is temporarily reset by the first emsg() call
+ * during an expression evaluation, and "cause_abort" is used instead.  It might
+ * be necessary to restore "force_abort" even before the throw point for the
+ * error message has been reached.  update_force_abort() should be called then.
+ */
+    void
+update_force_abort()
+{
+    if (cause_abort)
+	force_abort = TRUE;
+}
+
+/*
+ * Return TRUE if a command with a subcommand resulting in "retcode" should
+ * abort the script processing.  Can be used to suppress an autocommand after
+ * execution of a failing subcommand as long as the error message has not been
+ * displayed and actually caused the abortion.
+ */
+    int
+should_abort(retcode)
+    int		retcode;
+{
+    return ((retcode == FAIL && trylevel != 0 && !emsg_silent) || aborting());
+}
+
+/*
+ * Return TRUE if a function with the "abort" flag should not be considered
+ * ended on an error.  This means that parsing commands is continued in order
+ * to find finally clauses to be executed, and that some errors in skipped
+ * commands are still reported.
+ */
+    int
+aborted_in_try()
+{
+    /* This function is only called after an error.  In this case, "force_abort"
+     * determines whether searching for finally clauses is necessary. */
+    return force_abort;
+}
+
+/*
+ * cause_errthrow(): Cause a throw of an error exception if appropriate.
+ * Return TRUE if the error message should not be displayed by emsg().
+ * Sets "ignore", if the emsg() call should be ignored completely.
+ *
+ * When several messages appear in the same command, the first is usually the
+ * most specific one and used as the exception value.  The "severe" flag can be
+ * set to TRUE, if a later but severer message should be used instead.
+ */
+    int
+cause_errthrow(mesg, severe, ignore)
+    char_u	*mesg;
+    int		severe;
+    int		*ignore;
+{
+    struct msglist *elem;
+    struct msglist **plist;
+
+    /*
+     * Do nothing when displaying the interrupt message or reporting an uncaught
+     * exception (which has already been discarded then) at the top level.  Also
+     * when no exception can be thrown.  The message will be displayed by
+     * emsg().
+     */
+    if (suppress_errthrow)
+	return FALSE;
+
+    /*
+     * If emsg() has not been called previously, temporarily reset "force_abort"
+     * until the throw point for error messages has been reached.  This ensures
+     * that aborting() returns the same value for all errors that appear in the
+     * same command.  This means particularly that for parsing errors during
+     * expression evaluation emsg() will be called multiply, even when the
+     * expression is evaluated from a finally clause that was activated due to
+     * an aborting error, interrupt, or exception.
+     */
+    if (!did_emsg)
+    {
+	cause_abort = force_abort;
+	force_abort = FALSE;
+    }
+
+    /*
+     * If no try conditional is active and no exception is being thrown and
+     * there has not been an error in a try conditional or a throw so far, do
+     * nothing (for compatibility of non-EH scripts).  The message will then be
+     * displayed by emsg().  When ":silent!" was used and we are not currently
+     * throwing an exception, do nothing.  The message text will then be stored
+     * to v:errmsg by emsg() without displaying it.
+     */
+    if (((trylevel == 0 && !cause_abort) || emsg_silent) && !did_throw)
+	return FALSE;
+
+    /*
+     * Ignore an interrupt message when inside a try conditional or when an
+     * exception is being thrown or when an error in a try conditional or throw
+     * has been detected previously.  This is important in order that an
+     * interrupt exception is catchable by the innermost try conditional and
+     * not replaced by an interrupt message error exception.
+     */
+    if (mesg == (char_u *)_(e_interr))
+    {
+	*ignore = TRUE;
+	return TRUE;
+    }
+
+    /*
+     * Ensure that all commands in nested function calls and sourced files
+     * are aborted immediately.
+     */
+    cause_abort = TRUE;
+
+    /*
+     * When an exception is being thrown, some commands (like conditionals) are
+     * not skipped.  Errors in those commands may affect what of the subsequent
+     * commands are regarded part of catch and finally clauses.  Catching the
+     * exception would then cause execution of commands not intended by the
+     * user, who wouldn't even get aware of the problem.  Therefor, discard the
+     * exception currently being thrown to prevent it from being caught.  Just
+     * execute finally clauses and terminate.
+     */
+    if (did_throw)
+    {
+	/* When discarding an interrupt exception, reset got_int to prevent the
+	 * same interrupt being converted to an exception again and discarding
+	 * the error exception we are about to throw here. */
+	if (current_exception->type == ET_INTERRUPT)
+	    got_int = FALSE;
+	discard_current_exception();
+    }
+
+#ifdef THROW_TEST
+    if (!THROW_ON_ERROR)
+    {
+	/*
+	 * Print error message immediately without searching for a matching
+	 * catch clause; just finally clauses are executed before the script
+	 * is terminated.
+	 */
+	return FALSE;
+    }
+    else
+#endif
+    {
+	/*
+	 * Prepare the throw of an error exception, so that everything will
+	 * be aborted (except for executing finally clauses), until the error
+	 * exception is caught; if still uncaught at the top level, the error
+	 * message will be displayed and the script processing terminated
+	 * then.  -  This function has no access to the conditional stack.
+	 * Thus, the actual throw is made after the failing command has
+	 * returned.  -  Throw only the first of several errors in a row, except
+	 * a severe error is following.
+	 */
+	if (msg_list != NULL)
+	{
+	    plist = msg_list;
+	    while (*plist != NULL)
+		plist = &(*plist)->next;
+
+	    elem = (struct msglist *)alloc((unsigned)sizeof(struct msglist));
+	    if (elem == NULL)
+	    {
+		suppress_errthrow = TRUE;
+		EMSG(_(e_outofmem));
+	    }
+	    else
+	    {
+		elem->msg = vim_strsave(mesg);
+		if (elem->msg == NULL)
+		{
+		    vim_free(elem);
+		    suppress_errthrow = TRUE;
+		    EMSG(_(e_outofmem));
+		}
+		else
+		{
+		    elem->next = NULL;
+		    elem->throw_msg = NULL;
+		    *plist = elem;
+		    if (plist == msg_list || severe)
+		    {
+			char_u	    *tmsg;
+
+			/* Skip the extra "Vim " prefix for message "E458". */
+			tmsg = elem->msg;
+			if (STRNCMP(tmsg, "Vim E", 5) == 0
+				&& VIM_ISDIGIT(tmsg[5])
+				&& VIM_ISDIGIT(tmsg[6])
+				&& VIM_ISDIGIT(tmsg[7])
+				&& tmsg[8] == ':'
+				&& tmsg[9] == ' ')
+			    (*msg_list)->throw_msg = &tmsg[4];
+			else
+			    (*msg_list)->throw_msg = tmsg;
+		    }
+		}
+	    }
+	}
+	return TRUE;
+    }
+}
+
+/*
+ * Free a "msg_list" and the messages it contains.
+ */
+    static void
+free_msglist(l)
+    struct msglist  *l;
+{
+    struct msglist  *messages, *next;
+
+    messages = l;
+    while (messages != NULL)
+    {
+	next = messages->next;
+	vim_free(messages->msg);
+	vim_free(messages);
+	messages = next;
+    }
+}
+
+/*
+ * Throw the message specified in the call to cause_errthrow() above as an
+ * error exception.  If cstack is NULL, postpone the throw until do_cmdline()
+ * has returned (see do_one_cmd()).
+ */
+    void
+do_errthrow(cstack, cmdname)
+    struct condstack	*cstack;
+    char_u		*cmdname;
+{
+    /*
+     * Ensure that all commands in nested function calls and sourced files
+     * are aborted immediately.
+     */
+    if (cause_abort)
+    {
+	cause_abort = FALSE;
+	force_abort = TRUE;
+    }
+
+    /* If no exception is to be thrown or the conversion should be done after
+     * returning to a previous invocation of do_one_cmd(), do nothing. */
+    if (*msg_list == NULL)
+	return;
+
+    if (throw_exception(*msg_list, ET_ERROR, cmdname) == FAIL)
+	free_msglist(*msg_list);
+    else
+    {
+	if (cstack != NULL)
+	    do_throw(cstack);
+	else
+	    need_rethrow = TRUE;
+    }
+    *msg_list = NULL;
+}
+
+/*
+ * do_intthrow(): Replace the current exception by an interrupt or interrupt
+ * exception if appropriate.  Return TRUE if the current exception is discarded,
+ * FALSE otherwise.
+ */
+    int
+do_intthrow(cstack)
+    struct condstack	*cstack;
+{
+    /*
+     * If no interrupt occurred or no try conditional is active and no exception
+     * is being thrown, do nothing (for compatibility of non-EH scripts).
+     */
+    if (!got_int || (trylevel == 0 && !did_throw))
+	return FALSE;
+
+#ifdef THROW_TEST	/* avoid warning for condition always true */
+    if (!THROW_ON_INTERRUPT)
+    {
+	/*
+	 * The interrupt aborts everything except for executing finally clauses.
+	 * Discard any user or error or interrupt exception currently being
+	 * thrown.
+	 */
+	if (did_throw)
+	    discard_current_exception();
+    }
+    else
+#endif
+    {
+	/*
+	 * Throw an interrupt exception, so that everything will be aborted
+	 * (except for executing finally clauses), until the interrupt exception
+	 * is caught; if still uncaught at the top level, the script processing
+	 * will be terminated then.  -  If an interrupt exception is already
+	 * being thrown, do nothing.
+	 *
+	 */
+	if (did_throw)
+	{
+	    if (current_exception->type == ET_INTERRUPT)
+		return FALSE;
+
+	    /* An interrupt exception replaces any user or error exception. */
+	    discard_current_exception();
+	}
+	if (throw_exception("Vim:Interrupt", ET_INTERRUPT, NULL) != FAIL)
+	    do_throw(cstack);
+    }
+
+    return TRUE;
+}
+
+
+/*
+ * Throw a new exception.  Return FAIL when out of memory or it was tried to
+ * throw an illegal user exception.  "value" is the exception string for a user
+ * or interrupt exception, or points to a message list in case of an error
+ * exception.
+ */
+    static int
+throw_exception(value, type, cmdname)
+    void	*value;
+    int		type;
+    char_u	*cmdname;
+{
+    except_T	*excp;
+    char_u	*p, *mesg, *val;
+    int		cmdlen;
+
+    /*
+     * Disallow faking Interrupt or error exceptions as user exceptions.  They
+     * would be treated differently from real interrupt or error exceptions when
+     * no active try block is found, see do_cmdline().
+     */
+    if (type == ET_USER)
+    {
+	if (STRNCMP((char_u *)value, "Vim", 3) == 0 &&
+		(((char_u *)value)[3] == NUL || ((char_u *)value)[3] == ':' ||
+		 ((char_u *)value)[3] == '('))
+	{
+	    EMSG(_("E608: Cannot :throw exceptions with 'Vim' prefix"));
+	    goto fail;
+	}
+    }
+
+    excp = (except_T *)alloc((unsigned)sizeof(except_T));
+    if (excp == NULL)
+	goto nomem;
+
+    if (type == ET_ERROR)
+    {
+	/* Store the original message and prefix the exception value with
+	 * "Vim:" or, if a command name is given, "Vim(cmdname):". */
+	excp->messages = (struct msglist *)value;
+	mesg = excp->messages->throw_msg;
+	if (cmdname != NULL && *cmdname != NUL)
+	{
+	    cmdlen = STRLEN(cmdname);
+	    excp->value = vim_strnsave((char_u *)"Vim(",
+					   4 + cmdlen + 2 + (int)STRLEN(mesg));
+	    if (excp->value == NULL)
+		goto nomem;
+	    STRCPY(&excp->value[4], cmdname);
+	    STRCPY(&excp->value[4 + cmdlen], "):");
+	    val = excp->value + 4 + cmdlen + 2;
+	}
+	else
+	{
+	    excp->value = vim_strnsave((char_u *)"Vim:", 4 + (int)STRLEN(mesg));
+	    if (excp->value == NULL)
+		goto nomem;
+	    val = excp->value + 4;
+	}
+
+	/* msg_add_fname may have been used to prefix the message with a file
+	 * name in quotes.  In the exception value, put the file name in
+	 * parentheses and move it to the end. */
+	for (p = mesg; ; p++)
+	{
+	    if (*p == NUL
+		    || (*p == 'E'
+			&& VIM_ISDIGIT(p[1])
+			&& (p[2] == ':'
+			    || (VIM_ISDIGIT(p[2])
+				&& (p[3] == ':'
+				    || (VIM_ISDIGIT(p[3])
+					&& p[4] == ':'))))))
+	    {
+		if (*p == NUL || p == mesg)  /* 'E123' missing or at beginning */
+		    STRCAT(val, mesg);
+		else
+		{
+		    /* '"filename" E123: message text' */
+		    if (mesg[0] != '"' || p-2 < &mesg[1] ||
+			    p[-2] != '"' || p[-1] != ' ')
+			/* "E123:" is part of the file name. */
+			continue;
+
+		    STRCAT(val, p);
+		    p[-2] = NUL;
+		    sprintf((char *)(val + STRLEN(p)), " (%s)", &mesg[1]);
+		    p[-2] = '"';
+		}
+		break;
+	    }
+	}
+    }
+    else
+	excp->value = value;
+
+    excp->type = type;
+    excp->throw_name = vim_strsave(sourcing_name == NULL
+					      ? (char_u *)"" : sourcing_name);
+    if (excp->throw_name == NULL)
+    {
+	if (type == ET_ERROR)
+	    vim_free(excp->value);
+	goto nomem;
+    }
+    excp->throw_lnum = sourcing_lnum;
+
+    if (p_verbose >= 13 || debug_break_level > 0)
+    {
+	int	save_msg_silent = msg_silent;
+
+	if (debug_break_level > 0)
+	    msg_silent = FALSE;		/* display messages */
+	++no_wait_return;
+	msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
+	msg_str((char_u *)_("Exception thrown: %s"), excp->value);
+	msg_puts((char_u *)"\n");   /* don't overwrite this either */
+	cmdline_row = msg_row;
+	--no_wait_return;
+	if (debug_break_level > 0)
+	    msg_silent = save_msg_silent;
+    }
+
+    current_exception = excp;
+    return OK;
+
+nomem:
+    vim_free(excp);
+    suppress_errthrow = TRUE;
+    EMSG(_(e_outofmem));
+fail:
+    current_exception = NULL;
+    return FAIL;
+}
+
+/*
+ * Discard an exception.  "was_finished" is set when the exception has been
+ * caught and the catch clause has been ended normally.
+ */
+    static void
+discard_exception(excp, was_finished)
+    except_T		*excp;
+    int			was_finished;
+{
+    char_u		*saved_IObuff;
+
+    if (excp == NULL)
+    {
+	EMSG(_(e_internal));
+	return;
+    }
+
+    if (p_verbose >= 13 || debug_break_level > 0)
+    {
+	int	save_msg_silent = msg_silent;
+
+	saved_IObuff = vim_strsave(IObuff);
+	if (debug_break_level > 0)
+	    msg_silent = FALSE;		/* display messages */
+	++no_wait_return;
+	msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
+	msg_str(was_finished
+		    ? (char_u *)_("Exception finished: %s")
+		    : (char_u *)_("Exception discarded: %s"),
+		excp->value);
+	msg_puts((char_u *)"\n");   /* don't overwrite this either */
+	cmdline_row = msg_row;
+	--no_wait_return;
+	if (debug_break_level > 0)
+	    msg_silent = save_msg_silent;
+	STRCPY(IObuff, saved_IObuff);
+	vim_free(saved_IObuff);
+    }
+    if (excp->type != ET_INTERRUPT)
+	vim_free(excp->value);
+    if (excp->type == ET_ERROR)
+	free_msglist(excp->messages);
+    vim_free(excp->throw_name);
+    vim_free(excp);
+}
+
+/*
+ * Discard the exception currently being thrown.
+ */
+    void
+discard_current_exception()
+{
+    discard_exception(current_exception, FALSE);
+    current_exception = NULL;
+    did_throw = FALSE;
+    need_rethrow = FALSE;
+}
+
+/*
+ * Put an exception on the caught stack.
+ */
+    static void
+catch_exception(excp)
+    except_T	*excp;
+{
+    excp->caught = caught_stack;
+    caught_stack = excp;
+    set_vim_var_string(VV_EXCEPTION, excp->value, -1);
+    if (*excp->throw_name != NUL)
+    {
+	if (excp->throw_lnum != 0)
+	    sprintf((char *)IObuff, _("%s, line %ld"), excp->throw_name,
+		    (long)excp->throw_lnum);
+	else
+	    STRCPY(IObuff, excp->throw_name);
+	set_vim_var_string(VV_THROWPOINT, IObuff, -1);
+    }
+    else
+	/* throw_name not set on an exception from a command that was typed. */
+	set_vim_var_string(VV_THROWPOINT, NULL, -1);
+
+    if (p_verbose >= 13 || debug_break_level > 0)
+    {
+	int	save_msg_silent = msg_silent;
+
+	if (debug_break_level > 0)
+	    msg_silent = FALSE;		/* display messages */
+	++no_wait_return;
+	msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
+	msg_str((char_u *)_("Exception caught: %s"), excp->value);
+	msg_puts((char_u *)"\n");   /* don't overwrite this either */
+	cmdline_row = msg_row;
+	--no_wait_return;
+	if (debug_break_level > 0)
+	    msg_silent = save_msg_silent;
+    }
+}
+
+/*
+ * Remove an exception from the caught stack.
+ */
+    static void
+finish_exception(excp)
+    except_T	*excp;
+{
+    if (excp != caught_stack)
+	EMSG(_(e_internal));
+    caught_stack = caught_stack->caught;
+    if (caught_stack != NULL)
+    {
+	set_vim_var_string(VV_EXCEPTION, caught_stack->value, -1);
+	if (*caught_stack->throw_name != NUL)
+	{
+	    if (caught_stack->throw_lnum != 0)
+		sprintf((char *)IObuff,
+			_("%s, line %ld"), caught_stack->throw_name,
+			(long)caught_stack->throw_lnum);
+	    else
+		STRCPY(IObuff, caught_stack->throw_name);
+	    set_vim_var_string(VV_THROWPOINT, IObuff, -1);
+	}
+	else
+	    /* throw_name not set on an exception from a command that was
+	     * typed. */
+	    set_vim_var_string(VV_THROWPOINT, NULL, -1);
+    }
+    else
+    {
+	set_vim_var_string(VV_EXCEPTION, NULL, -1);
+	set_vim_var_string(VV_THROWPOINT, NULL, -1);
+    }
+
+    /* Discard the exception, but use the finish message for 'verbose'. */
+    discard_exception(excp, TRUE);
+}
+
+/*
+ * Flags specifying the message displayed by report_pending.
+ */
+#define RP_MAKE		0
+#define RP_RESUME	1
+#define RP_DISCARD	2
+
+/*
+ * Report information about something pending in a finally clause if required by
+ * the 'verbose' option or when debugging.  "action" tells whether something is
+ * made pending or something pending is resumed or discarded.  "pending" tells
+ * what is pending.  "value" specifies the return value for a pending ":return"
+ * or the exception value for a pending exception.
+ */
+    static void
+report_pending(action, pending, value)
+    int		action;
+    int		pending;
+    void	*value;
+{
+    char_u	*mesg;
+    char	*s;
+    int		save_msg_silent;
+
+
+    switch (action)
+    {
+	case RP_MAKE:
+	    mesg = (char_u *)_("%s made pending");
+	    break;
+	case RP_RESUME:
+	    mesg = (char_u *)_("%s resumed");
+	    break;
+	/* case RP_DISCARD: */
+	default:
+	    mesg = (char_u *)_("%s discarded");
+	    break;
+    }
+
+    switch (pending)
+    {
+	case CSTP_NONE:
+	    return;
+
+	case CSTP_CONTINUE:
+	    s = ":continue";
+	    break;
+	case CSTP_BREAK:
+	    s = ":break";
+	    break;
+	case CSTP_FINISH:
+	    s = ":finish";
+	    break;
+	case CSTP_RETURN:
+	    /* ":return" command producing value, allocated */
+	    s = (char *)get_return_cmd(value);
+	    break;
+
+	default:
+	    if (pending & CSTP_THROW)
+	    {
+		sprintf((char *)IObuff, (char *)mesg, _("Exception"));
+		mesg = vim_strnsave(IObuff, (int)STRLEN(IObuff) + 4);
+		STRCAT(mesg, ": %s");
+		s = (char *)((except_T *)value)->value;
+	    }
+	    else if ((pending & CSTP_ERROR) && (pending & CSTP_INTERRUPT))
+		s = _("Error and interrupt");
+	    else if (pending & CSTP_ERROR)
+		s = _("Error");
+	    else /* if (pending & CSTP_INTERRUPT) */
+		s = _("Interrupt");
+    }
+
+    save_msg_silent = msg_silent;
+    if (debug_break_level > 0)
+	msg_silent = FALSE;	/* display messages */
+    ++no_wait_return;
+    msg_scroll = TRUE;		/* always scroll up, don't overwrite */
+    msg_str(mesg, (char_u *)s);
+    msg_puts((char_u *)"\n");   /* don't overwrite this either */
+    cmdline_row = msg_row;
+    --no_wait_return;
+    if (debug_break_level > 0)
+	msg_silent = save_msg_silent;
+
+    if (pending == CSTP_RETURN)
+	vim_free(s);
+    else if (pending & CSTP_THROW)
+	vim_free(mesg);
+}
+
+/*
+ * If something is made pending in a finally clause, report it if required by
+ * the 'verbose' option or when debugging.
+ */
+    void
+report_make_pending(pending, value)
+    int		pending;
+    void	*value;
+{
+    if (p_verbose >= 14 || debug_break_level > 0)
+	report_pending(RP_MAKE, pending, value);
+}
+
+/*
+ * If something pending in a finally clause is resumed at the ":endtry", report
+ * it if required by the 'verbose' option or when debugging.
+ */
+    void
+report_resume_pending(pending, value)
+    int		pending;
+    void	*value;
+{
+    if (p_verbose >= 14 || debug_break_level > 0)
+	report_pending(RP_RESUME, pending, value);
+}
+
+/*
+ * If something pending in a finally clause is discarded, report it if required
+ * by the 'verbose' option or when debugging.
+ */
+    void
+report_discard_pending(pending, value)
+    int		pending;
+    void	*value;
+{
+    if (p_verbose >= 14 || debug_break_level > 0)
+	report_pending(RP_DISCARD, pending, value);
+}
+
+
+/*
+ * ":if".
+ */
+    void
+ex_if(eap)
+    exarg_T	*eap;
+{
+    int		error;
+    int		skip;
+    int		result;
+    struct condstack	*cstack = eap->cstack;
+
+    if (cstack->cs_idx == CSTACK_LEN - 1)
+	eap->errmsg = (char_u *)N_("E579: :if nesting too deep");
+    else
+    {
+	++cstack->cs_idx;
+	cstack->cs_flags[cstack->cs_idx] = 0;
+
+	/*
+	 * Don't do something after an error, interrupt, or throw, or when there
+	 * is a surrounding conditional and it was not active.
+	 */
+	skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
+		&& !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
+
+	result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+
+	if (!skip && !error)
+	{
+	    if (result)
+		cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE;
+	}
+	else
+	    /* set TRUE, so this conditional will never get active */
+	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
+    }
+}
+
+/*
+ * ":endif".
+ */
+    void
+ex_endif(eap)
+    exarg_T	*eap;
+{
+    did_endif = TRUE;
+    if (eap->cstack->cs_idx < 0
+	    || (eap->cstack->cs_flags[eap->cstack->cs_idx] &
+		(CSF_WHILE | CSF_TRY)))
+	eap->errmsg = (char_u *)N_("E580: :endif without :if");
+    else
+    {
+	/*
+	 * When debugging or a breakpoint was encountered, display the debug
+	 * prompt (if not already done).  This shows the user that an ":endif"
+	 * is executed when the ":if" or a previous ":elseif" was not TRUE.
+	 * Handle a ">quit" debug command as if an interrupt had occurred before
+	 * the ":endif".  That is, throw an interrupt exception if appropriate.
+	 * Doing this here prevents an exception for a parsing error being
+	 * discarded by throwing the interrupt exception later on.
+	 */
+	if (!(eap->cstack->cs_flags[eap->cstack->cs_idx] & CSF_TRUE) &&
+		dbg_check_skipped(eap))
+	    (void)do_intthrow(eap->cstack);
+
+	--eap->cstack->cs_idx;
+    }
+}
+
+/*
+ * ":else" and ":elseif".
+ */
+    void
+ex_else(eap)
+    exarg_T	*eap;
+{
+    int		error;
+    int		skip;
+    int		result;
+    struct condstack	*cstack = eap->cstack;
+
+    /*
+     * Don't do something after an error, interrupt, or throw, or when there is
+     * a surrounding conditional and it was not active.
+     */
+    skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
+	    && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
+
+    if (cstack->cs_idx < 0
+	    || (cstack->cs_flags[cstack->cs_idx] & (CSF_WHILE | CSF_TRY)))
+    {
+	if (eap->cmdidx == CMD_else)
+	{
+	    eap->errmsg = (char_u *)N_("E581: :else without :if");
+	    return;
+	}
+	eap->errmsg = (char_u *)N_("E582: :elseif without :if");
+	skip = TRUE;
+    }
+    else if (cstack->cs_flags[cstack->cs_idx] & CSF_ELSE)
+    {
+	if (eap->cmdidx == CMD_else)
+	{
+	    eap->errmsg = (char_u *)N_("E583: multiple :else");
+	    return;
+	}
+	eap->errmsg = (char_u *)N_("E584: :elseif after :else");
+	skip = TRUE;
+    }
+
+    /* if skipping or the ":if" was TRUE, reset ACTIVE, otherwise set it */
+    if (skip || cstack->cs_flags[cstack->cs_idx] & CSF_TRUE)
+    {
+	if (eap->errmsg == NULL)
+	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
+	skip = TRUE;	/* don't evaluate an ":elseif" */
+    }
+    else
+	cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE;
+
+    /*
+     * When debugging or a breakpoint was encountered, display the debug prompt
+     * (if not already done).  This shows the user that an ":else" or ":elseif"
+     * is executed when the ":if" or previous ":elseif" was not TRUE.  Handle
+     * a ">quit" debug command as if an interrupt had occurred before the
+     * ":else" or ":elseif".  That is, set "skip" and throw an interrupt
+     * exception if appropriate.  Doing this here prevents that an exception
+     * for a parsing errors is discarded when throwing the interrupt exception
+     * later on.
+     */
+    if (!skip && dbg_check_skipped(eap) && got_int)
+    {
+	(void)do_intthrow(cstack);
+	skip = TRUE;
+    }
+
+    if (eap->cmdidx == CMD_elseif)
+    {
+	result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+	/* When throwing error exceptions, we want to throw always the first
+	 * of several errors in a row.  This is what actually happens when
+	 * a conditional error was detected above and there is another failure
+	 * when parsing the expression.  Since the skip flag is set in this
+	 * case, the parsing error will be ignored by emsg(). */
+
+	if (!skip && !error)
+	{
+	    if (result)
+		cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE;
+	    else
+		cstack->cs_flags[cstack->cs_idx] = 0;
+	}
+	else if (eap->errmsg == NULL)
+	    /* set TRUE, so this conditional will never get active */
+	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
+    }
+    else
+	cstack->cs_flags[cstack->cs_idx] |= CSF_ELSE;
+}
+
+/*
+ * Handle ":while".
+ */
+    void
+ex_while(eap)
+    exarg_T	*eap;
+{
+    int		error;
+    int		skip;
+    int		result;
+    struct condstack	*cstack = eap->cstack;
+
+    if (cstack->cs_idx == CSTACK_LEN - 1)
+	eap->errmsg = (char_u *)N_("E585: :while nesting too deep");
+    else
+    {
+	/*
+	 * cs_had_while is set when we have jumped back from the matching
+	 * ":endwhile".  When not set, need to initialise this cstack entry.
+	 */
+	if (!cstack->cs_had_while)
+	{
+	    ++cstack->cs_idx;
+	    ++cstack->cs_whilelevel;
+	    cstack->cs_line[cstack->cs_idx] = -1;
+	}
+	cstack->cs_flags[cstack->cs_idx] = CSF_WHILE;
+
+	/*
+	 * Don't do something after an error, interrupt, or throw, or when there
+	 * is a surrounding conditional and it was not active.
+	 */
+	skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
+		&& !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
+	result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+
+	/*
+	 * If this cstack entry was just initialised and is active, set
+	 * cs_had_while flag, so do_cmdline() will set the line number
+	 * in cs_line[].
+	 */
+	if (!skip && !error && result)
+	{
+	    cstack->cs_flags[cstack->cs_idx] |= CSF_ACTIVE | CSF_TRUE;
+	    cstack->cs_had_while = !cstack->cs_had_while;
+	}
+	else
+	{
+	    cstack->cs_had_while = FALSE;
+	    /* If the ":while" evaluates to FALSE, show the debug prompt at the
+	     * ":endwhile" as if there was a ":break" in a ":while" evaluating
+	     * to TRUE. */
+	    if (!skip && !error)
+		cstack->cs_flags[cstack->cs_idx] |= CSF_TRUE;
+	}
+    }
+}
+
+/*
+ * ":continue"
+ */
+    void
+ex_continue(eap)
+    exarg_T	*eap;
+{
+    int		idx;
+    struct condstack	*cstack = eap->cstack;
+
+    if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0)
+	eap->errmsg = (char_u *)N_("E586: :continue without :while");
+    else
+    {
+	/* Try to find the matching ":while".  This might stop at a try
+	 * conditional not in its finally clause (which is then to be executed
+	 * next).  Therefor, inactivate all conditionals except the ":while"
+	 * itself (if reached). */
+	idx = cleanup_conditionals(cstack, CSF_WHILE, FALSE);
+	if ((cstack->cs_flags[idx] & CSF_WHILE))
+	{
+	    if (cstack->cs_idx > idx)
+		rewind_conditionals(cstack, idx, CSF_TRY, &cstack->cs_trylevel);
+
+	    /*
+	     * Set cs_had_continue, so do_cmdline() will jump back to the
+	     * matching ":while".
+	     */
+	    cstack->cs_had_continue = TRUE;	/* let do_cmdline() handle it */
+	}
+	else
+	{
+	    /* If a try conditional not in its finally clause is reached first,
+	     * make the ":continue" pending for execution at the ":endtry". */
+	    cstack->cs_pending[idx] = CSTP_CONTINUE;
+	    report_make_pending(CSTP_CONTINUE, NULL);
+	}
+    }
+}
+
+/*
+ * ":break"
+ */
+    void
+ex_break(eap)
+    exarg_T	*eap;
+{
+    int		idx;
+    struct condstack	*cstack = eap->cstack;
+
+    if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0)
+	eap->errmsg = (char_u *)N_("E587: :break without :while");
+    else
+    {
+	/* Inactivate conditionals until the matching ":while" or a try
+	 * conditional not in its finally clause (which is then to be
+	 * executed next) is found.  In the latter case, make the ":break"
+	 * pending for execution at the ":endtry". */
+	idx = cleanup_conditionals(cstack, CSF_WHILE, TRUE);
+	if (!(cstack->cs_flags[idx] & CSF_WHILE))
+	{
+	    cstack->cs_pending[idx] = CSTP_BREAK;
+	    report_make_pending(CSTP_BREAK, NULL);
+	}
+    }
+}
+
+/*
+ * ":endwhile"
+ */
+    void
+ex_endwhile(eap)
+    exarg_T	*eap;
+{
+    struct condstack	*cstack = eap->cstack;
+    int		idx;
+
+    if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0)
+	eap->errmsg = e_while;
+    else
+    {
+	if (!(cstack->cs_flags[cstack->cs_idx] & CSF_WHILE))