5 carp - warn of errors (from perspective of caller)
7 croak - die of errors (from perspective of caller)
9 confess - die of errors with stack backtrace
14 croak "We're outta here!";
18 The Carp routines are useful in your own modules because
19 they act like die() or warn(), but report where the error
20 was in the code they were called from. Thus if you have a
21 routine Foo() that has a carp() in it, then the carp()
22 will report the error as occurring where Foo() was called,
23 not where carp() was called.
27 # This package implements handy routines for modules that wish to throw
28 # exceptions outside of the current package.
30 $CarpLevel = 0; # How many extra package levels to skip on carp.
31 $MaxEvalLen = 0; # How much eval '...text...' to show. 0 = all.
32 $MaxArgLen = 64; # How much of each argument to print. 0 = all.
33 $MaxArgNums = 8; # How many arguments to print. 0 = all.
37 @EXPORT = qw(confess croak carp);
42 my $i = 1 + $CarpLevel;
43 my ($pack,$file,$line,$sub,$hargs,$eval,$require);
45 while (do { { package DB; @a = caller($i++) } } ) {
46 ($pack,$file,$line,$sub,$hargs,undef,$eval,$require) = @a;
47 if ($error =~ m/\n$/) {
52 $sub = "require $eval";
54 $eval =~ s/([\\\'])/\\$1/g;
55 if ($MaxEvalLen && length($eval) > $MaxEvalLen) {
56 substr($eval,$MaxEvalLen) = '...';
58 $sub = "eval '$eval'";
60 } elsif ($sub eq '(eval)') {
64 @a = @DB::args; # must get local copy of args
65 if ($MaxArgNums and @a > $MaxArgNums) {
71 substr($_,$MaxArgLen) = '...' if $MaxArgLen and $MaxArgLen < length;
72 s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/;
73 s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
74 s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
76 $sub .= '(' . join(', ', @a) . ')';
78 $mess .= "\t$sub " if $error eq "called";
79 $mess .= "$error at $file line $line\n";
86 sub shortmess { # Short-circuit &longmess if called via multiple packages
87 my $error = $_[0]; # Instead of "shift"
88 my ($prevpack) = caller(1);
89 my $extra = $CarpLevel;
91 my ($pack,$file,$line);
92 my %isa = ($prevpack,1);
94 @isa{@{"${prevpack}::ISA"}} = ()
95 if(defined @{"${prevpack}::ISA"});
97 while (($pack,$file,$line) = caller($i++)) {
98 if(defined @{$pack . "::ISA"}) {
99 my @i = @{$pack . "::ISA"};
103 if(exists $i{$prevpack} || exists $isa{$pack});
107 if(exists $isa{$pack});
111 @isa{@{$pack . "::ISA"}} = ()
112 if(defined @{$pack . "::ISA"});
115 return "$error at $file line $line\n";
125 sub confess { die longmess @_; }
126 sub croak { die shortmess @_; }
127 sub carp { warn shortmess @_; }