Re^2: tied, or modified?

Hmm, Perl 5.8.9 gives me

$ perl -MO=Deparse -e 'tied sub {}->()'
tied {sub {
    
}
}->();
-e syntax OK
[download]

which gives a different error:

$ perl -e 'tied { sub {} }->()'
Not a subroutine reference at -e line 1.
[download]

The code you mention doesn't compile:

$ perl -e 'tied { sub {}->() }'
Can't modify anonymous hash ({}) in tied at -e line 1, at EOF
Execution of -e aborted due to compilation errors.
[download]

Thanks for taking the time to think about this. I've cut and pasted these straight from the command line to avoid further incidents. :-)

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Re^3: tied, or modified? by ikegami (Patriarch) on Nov 13, 2009 at 23:40 UTC
which gives a different error: As it should. Like I said, it's a bug in Deparse. An anonymous hash is the `anonhash` opcode. `$ perl -MO=Concise,-exec -e'{}' 1 <0> enter 2 <;> nextstate(main 1 -e:1) v:{ 3 <0> pushmark s 4 <@> anonhash vK* 5 <@> leave[1 ref] vKP/REFC -e syntax OK` [download] Note the lack of `anonhash` in the code that's actually produced by `tied sub {}->()`. `$ perl -MO=Concise,-exec -e'tied sub {}->()' 1 <0> enter 2 <;> nextstate(main 2 -e:1) v:{ 3 <0> pushmark s 4 <0> pushmark sRM 5 <$> anoncode[CV ] lRM 6 <1> refgen sK/1 7 <1> rv2cv sK/NO() 8 <1> entersub[t2] sKRMS/NO(),TARG,1 9 <1> tied vK/1 a <@> leave[1 ref] vKP/REFC -e syntax OK` [download] Deparse is wrong to add an anon hash constructor. Therefore, trying to execute the output of Deparse makes no sense.	[reply] [d/l] [select]

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Re^3: tied, or modified?
by ikegami (Patriarch) on Nov 13, 2009 at 23:40 UTC

which gives a different error:

As it should. Like I said, it's a bug in Deparse.

An anonymous hash is the anonhash opcode.

$ perl -MO=Concise,-exec -e'{}'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <0> pushmark s
4  <@> anonhash vK*
5  <@> leave[1 ref] vKP/REFC
-e syntax OK
[download]

Note the lack of anonhash in the code that's actually produced by tied sub {}->().

$ perl -MO=Concise,-exec -e'tied sub {}->()'
1  <0> enter
2  <;> nextstate(main 2 -e:1) v:{
3  <0> pushmark s
4  <0> pushmark sRM
5  <$> anoncode[CV ] lRM
6  <1> refgen sK/1
7  <1> rv2cv sK/NO()
8  <1> entersub[t2] sKRMS/NO(),TARG,1
9  <1> tied vK/1
a  <@> leave[1 ref] vKP/REFC
-e syntax OK
[download]

Deparse is wrong to add an anon hash constructor. Therefore, trying to execute the output of Deparse makes no sense.

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