Rephrased:

B::Deparse thinks (and I expected) that parens have priority to capture function arguments and that

do('foo')->{'bar'};

is analogous to

(do 'foo') -> {bar}

but the weird parser rather sees

do ('foo' -> {bar})

see the difference in priority of parens around arguments by comparing print() vs do()

lanx@nc10-ubuntu:/tmp$ perl -MO=Concise, -e 'do ($foo)->{bar};' 9 <@> leave[1 ref] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v:{ ->3 8 <1> dofile vK/1 ->9 # do file 7 <2> helem sK/2 ->8 # hash-elem returns fi +le 5 <1> rv2hv[t2] sKR/1 ->6 4 <1> rv2sv sKPM/DREFHV,1 ->5 3 <#> gv[*foo] s ->4 6 <$> const[PV "bar"] s/BARE ->7 -e syntax OK lanx@nc10-ubuntu:/tmp$ perl -MO=Concise, -e 'print ($foo)->{bar};' 9 <@> leave[1 ref] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v:{ ->3 8 <2> helem vK/2 ->9 # hash-element 6 <1> rv2hv[t2] sKR/1 ->7 5 <@> print sK ->6 # print returns hashre +f 3 <0> pushmark s ->4 - <1> ex-rv2sv sK/1 ->5 4 <#> gvsv[*foo] s ->5 7 <$> const[PV "bar"] s/BARE ->8 -e syntax OK

just remember the common trap when people try writing something like

 print (caller)[5]

$ perl -c -e 'print (caller)[5]' syntax error at -e line 1, near ")[" -e had compilation errors.

while

$ perl -c -e 'do (L,I,S,T)[5]' -e syntax OK

Cheers Rolf

(addicted to the Perl Programming Language and ☆☆☆☆ :)


In reply to Re: B::Deparse weirdness (parser weirdness!) by LanX
in thread B::Deparse weirdness by choroba

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