summaryrefslogtreecommitdiffstats
path: root/doc/AllowExc.3
blob: 29e31be5e954c06945e39127508a3903a70bd9fc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
'\"
'\" Copyright (c) 1989-1993 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tcl_AllowExceptions 3 7.4 Tcl "Tcl Library Procedures"
.so man.macros
.BS
.SH NAME
Tcl_AllowExceptions \- allow all exceptions in next script evaluation
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
\fBTcl_AllowExceptions\fR(\fIinterp\fR)
.SH ARGUMENTS
.AS Tcl_Interp *interp
.AP Tcl_Interp *interp in
Interpreter in which script will be evaluated.
.BE

.SH DESCRIPTION
.PP
If a script is evaluated at top-level (i.e. no other scripts are
pending evaluation when the script is invoked), and if the script
terminates with a completion code other than \fBTCL_OK\fR, \fBTCL_ERROR\fR
or \fBTCL_RETURN\fR, then Tcl normally converts this into a \fBTCL_ERROR\fR
return with an appropriate message.  The particular script
evaluation procedures of Tcl that act in the manner are
\fBTcl_EvalObjEx\fR, \fBTcl_EvalObjv\fR, \fBTcl_Eval\fR, \fBTcl_EvalEx\fR,
\fBTcl_GlobalEval\fR, \fBTcl_GlobalEvalObj\fR and \fBTcl_VarEval\fR.
.PP
However, if \fBTcl_AllowExceptions\fR is invoked immediately before
calling one of those a procedures, then arbitrary completion
codes are permitted from the script, and they are returned without
modification.
This is useful in cases where the caller can deal with exceptions
such as \fBTCL_BREAK\fR or \fBTCL_CONTINUE\fR in a meaningful way.

.SH KEYWORDS
continue, break, exception, interpreter