Hi,

I'm testing an eval block. I want to imitate a situation in debug mode and for that I want to change $@ in debug mode to a different value. But the value in $@ does not seem to be changing.

Take a look at the following debug session: 

> perl -d -e ' eval { 1/0}; print $@; $@ = "nikhil"; print $@'

Loading DB routines from perl5db.pl version 1.32
Editor support available.

Enter h or `h h' for help, or `man perldebug' for more help.

main::(-e:1):    eval { 1/0}; print $@; $@ = "nikhil"; print $@
  DB<1>

  DB<1> n
main::(-e:1):    eval { 1/0}; print $@; $@ = "nikhil"; print $@
  DB<1> n
main::(-e:1):    eval { 1/0}; print $@; $@ = "nikhil"; print $@
  DB<1> n
Illegal division by zero at -e line 1.
main::(-e:1):    eval { 1/0}; print $@; $@ = "nikhil"; print $@
  DB<1> x $@
0  'Illegal division by zero at -e line 1.
'
  DB<2> $@ = "a"

  DB<3> x $@
0  'Illegal division by zero at -e line 1.
'
  DB<4> n
main::(-e:1):    eval { 1/0}; print $@; $@ = "nikhil"; print $@
  DB<4> x $@
0  'nikhil'
  DB<5>

[download]

I'm able to set $@ programmatically from the script but not in the debug shell. Is this a known perl feature/issue?

Please enlighten me.

Thanks,

Nikhil

In reply to Changing $@ in debug mode by nbokare

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