Re^4: shift on empty array in list context broken

well not really short and concise...

undef is/was IIRC meant to free memory.

though I can't reproduce any difference between an emptied and destroyed array.

list context different:

  DB<49> undef @x

  DB<50> x [ shift @x, splice @x,0,1 ]
0  ARRAY(0x34a5270)
   0  undef
  DB<51> @x=()

  DB<52> x [ shift @x, splice @x,0,1 ]
0  ARRAY(0x34a6c48)
   0  undef
  DB<53>
[download]

scalar context same

  DB<54> undef @x

  DB<55> x [ ($a=shift @x), ($b=splice @x,0,1) ]
0  ARRAY(0x34a6960)
   0  undef
   1  undef
  DB<56> @x=()

  DB<57> x [ ($a=shift @x), ($b=splice @x,0,1) ]
0  ARRAY(0x34a6f18)
   0  undef
   1  undef
[download]

Cheers Rolf
_{(addicted to the Perl Programming Language :)

Wikisyntax for the Monastery
FootballPerl is like chess, only without the dice}

Comment on Re^4: shift on empty array in list context broken Select or Download Code

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Re^5: shift on empty array in list context broken by Don Coyote (Hermit) on Jul 16, 2019 at 14:25 UTC
I am viewing the docs, `x [maxdepth] expr\n\tEvaluates its expression in list context ...`. Would this affect the interpretation of the contexts?	[reply] [d/l]
Re^6: shift on empty array in list context broken by LanX (Saint) on Jul 16, 2019 at 17:21 UTC
> Would this affect the interpretation of the contexts? No, the context of x is not propagated. the `[...,...]` is imposing list context `DB<50> x [ shift @x, splice @x,0,1 ] 0 ARRAY(0x34a5270) 0 undef` [download] to enforce scalar context I used a scalar assignment `DB<60> x [ ($a=shift @x), ($b=splice @x,0,1) ]` [download] if you have doubts enter a call to a sub which returns the context depending on `wantarray` Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l] [select]
Re^7: shift on empty array in list context broken (show context) by LanX (Saint) on Jul 17, 2019 at 11:59 UTC
> if you have doubts enter a call to a sub which returns the context depending on `wantarray` `DB<35> sub context { local $\="\n";print wantarray ? "list" : define +d wantarray ? "scalar" : "void";() } DB<36> x [ ($a= context), (context) ] scalar list 0 ARRAY(0x3466930) 0 undef DB<37>` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l]
Re^8: shift on empty array in list context broken (show context) by Don Coyote (Hermit) on Jul 18, 2019 at 14:22 UTC
Re^8: shift on empty array in list context broken (show context) by Don Coyote (Hermit) on Jul 20, 2019 at 16:43 UTC
Re^9: shift on empty array in list context broken (show context) by LanX (Saint) on Jul 20, 2019 at 19:31 UTC
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