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# assert.pl |
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# tchrist@convex.com (Tom Christiansen) |
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# |
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# Usage: |
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# |
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# &assert('@x > @y'); |
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# &assert('$var > 10', $var, $othervar, @various_info); |
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# |
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# That is, if the first expression evals false, we blow up. The |
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# rest of the args, if any, are nice to know because they will |
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# be printed out by &panic, which is just the stack-backtrace |
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# routine shamelessly borrowed from the perl debugger. |
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|
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sub assert { |
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&panic("ASSERTION BOTCHED: $_[$[]",$@) unless eval $_[$[]; |
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} |
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|
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sub panic { |
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package DB; |
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|
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select(STDERR); |
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|
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print "\npanic: @_\n"; |
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|
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exit 1 if $] <= 4.003; # caller broken |
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|
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# stack traceback gratefully borrowed from perl debugger |
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|
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local $_; |
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my $i; |
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my ($p,$f,$l,$s,$h,$a,@a,@frames); |
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for ($i = 0; ($p,$f,$l,$s,$h,$w) = caller($i); $i++) { |
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@a = @args; |
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for (@a) { |
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if (/^StB\000/ && length($_) == length($_main{'_main'})) { |
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$_ = sprintf("%s",$_); |
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} |
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else { |
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s/'/\\'/g; |
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s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/; |
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s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg; |
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s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg; |
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} |
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} |
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$w = $w ? '@ = ' : '$ = '; |
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$a = $h ? '(' . join(', ', @a) . ')' : ''; |
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push(@frames, "$w&$s$a from file $f line $l\n"); |
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} |
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for ($i=0; $i <= $#frames; $i++) { |
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print $frames[$i]; |
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} |
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exit 1; |
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} |
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|
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1; |
