PPI gets it right, its a string ... or is that "wrong" of ppi? ha
$ ppi_dumper -W shabba
PPI::Document
PPI::Statement
PPI::Token::Symbol '$x'
PPI::Token::Operator '=~'
PPI::Token::Quote::Single ''^something''
PPI::Token::Structure ';'
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My attention was directed to the post to which this is a reply. I'm not quite sure what the point of that post is, or why it was brought to my attention. All I can say is: Of course '^something' is a single-quoted string literal.
That doesn't mean it the code doesn't result in a regex match. We already know it does.
>perl -MO=Concise,-exec -e"$x =~ '^something'"
1 <0> enter
2 <;> nextstate(main 1 -e:1) v:{
3 <#> gvsv[*x] s
4 </> match(/"^something"/) vKS/RTIME
5 <@> leave[1 ref] vKP/REFC
-e syntax OK
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Sorry, I've been away for a while...
I pointed you to the wrong node. I replied to a subthread of the OP, and tried to highlight that to several responders, failing. I should have just left it to everyone's own devices to find the additions.
And it's been so long since I posted last in this thread, I can't remember what I was so excited to tell everyone about. Perhaps just that I initially thought the documentation left something out, but then discovered that it didn't, and could perhaps just be tied together a little tighter.
Cheers,
-QM
--
Quantum Mechanics: The dreams stuff is made of
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=~ with a string implies regex m//atch
Documented in doc:/perlop#Binding-Operators:
If the right argument is an expression rather than a search pattern, substitution, or transliteration, it is interpreted as a search pattern at run time.
-QM
--
Quantum Mechanics: The dreams stuff is made of
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> If the right argument is an expression rather than a search pattern,
True, but this doesn't apply here, it's literal a search pattern (i.e. compile time), the m is just optional:
Both generate exactly the same opcodes:
lanx@nc10-ubuntu:~$ perl -MO=Concise
'abc' =~ '\w{3}'
__DATA__
5 <@> leave[1 ref] vKP/REFC ->(end)
1 <0> enter ->2
2 <;> nextstate(main 1 -:1) v:{ ->3
4 </> match(/"\\w{3}"/) vKS/RTIME ->5
3 <$> const[PV "abc"] s ->4
- syntax OK
lanx@nc10-ubuntu:~$ perl -MO=Concise
'abc' =~ m'\w{3}'
__DATA__
5 <@> leave[1 ref] vKP/REFC ->(end)
1 <0> enter ->2
2 <;> nextstate(main 1 -:1) v:{ ->3
4 </> match(/"\\w{3}"/) vKS/RTIME ->5
3 <$> const[PV "abc"] s ->4
- syntax OK
"expressions evaluated at runtime" are things like variables or functions or do-blocks...
DB<103> $x= '\w{3}'
=> "\\w{3}"
DB<104> 'abc' =~ $x
=> 1
DB<105> sub regex { '\w{3}' }
DB<106> 'abc' =~ regex()
=> 1
Cheers Rolf
( addicted to the Perl Programming Language)
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OK, I see the light now.
<pedantic>
There's m//, and =~. m// can be used without =~ to match against $_, or with =~ to match against something else.
Without the presence of =~, m// can omit the m if the delimiter is //, else it is required.
=~ expects to see a match, substitution, or translation on the RHS, and assumes a match without m//, s//, y//, or tr//.
</pedantic>
And since m//, and =~ are 2 separate entities (that slightly overlap), the documentation doesn't tie these together explicitly (IMHO).
-QM
--
Quantum Mechanics: The dreams stuff is made of
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