This is annoying because I am also get used to use the debugger as a REPL (yes, I know Devel::REPL but I have not installed it everywhere and I usually have a perl debugger already open in my emacs).
After a lot of time avoiding the issue I asked it in stack overflow:
How to use perl 5.10 features inside the debugger?
and eldarerathis explained to me why
perl -dEbug
is not working:
[ eldarerathis]
I found a reference to the issue here, but it's about a year old. However, the relevant portion of the perl source hasn't changed since, and can be seen here.
Basically, the debugger is loaded before the
I found a reference to the issue here, but it's about a year old. However, the relevant portion of the perl source hasn't changed since, and can be seen here.
[...]
Basically, the debugger is loaded before the
-E
flag is processed, so the features aren't yet enabled when the debugger gets loaded. The gist of this is that you can't currently use -E
with the -d
command. If you want to use say
, switch
, or any other feature from the debug prompt, you have to do it like this:
DB<1> use feature 'say'; say "x"
x
Also seems that feature is lexically scoped so this does not work:
DB<19> use feature 'say'
DB<20> say 1
Number found where operator expected at (eval 41)[/homes/pmg/pmg-soft/local-perl/lib/5.12.1/perl5db.pl:638] line 2, near "say 1"
DB<20> say 1
Number found where operator expected at (eval 41)[/homes/pmg/pmg-soft/local-perl/lib/5.12.1/perl5db.pl:638] line 2, near "say 1"
but this does:
DB<21> use feature 'say';say 1
1
1
This is annoying because when debuggin perl >5.10 scripts, sometimes I need to fix a given/when, or a line with ~~ or copy-paste a line with say and it does not work :-(.
If someone has any idea how to use new Perl code features in the debugger command line please let me know or answer in stack overflow.