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Perl: the Markov chain saw

Re^2: Is this normal

by dave_the_m (Prior)
on Jan 06, 2012 at 23:30 UTC ( #946682=note: print w/replies, xml ) Need Help??

in reply to Re: Is this normal
in thread Is this normal

a non-match does not return 0. It returns the empty string
Strictly speaking, it returns PL_sv_no, which has both a numerical value of 0 and a string value of "":
$ perl5140 -MDevel::Peek -e 'Dump scalar(/x/)' SV = PVNV(0x275ee10) at 0xa26500 REFCNT = 2147483647 FLAGS = (IOK,NOK,POK,READONLY,pIOK,pNOK,pPOK) IV = 0 NV = 0 PV = 0x275ee00 ""\0 CUR = 0 LEN = 16


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Re^3: Is this normal
by JavaFan (Canon) on Jan 07, 2012 at 08:45 UTC
    You are correct. However, the OP is printing out the values, so the string value will be taken.

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