Re: When would you use qr// on a literal string?

it_says_BALLS_on_your forehead schreef:

I thought that qr was mainly used for pre-compiling variables into
regex patterns, but a colleague uses it like so:

my ( $name, $value ) = split qr/=/, $string;

Are there any benefits to doing this? He claims that the use of the
qr// op here can help capture an error if the STRING is not a valid
regex. Does this make any sense?

I don't see any difference in using /+/ or qr/+/, both give the same
error.
My gut feeling says that split does a precompile on a /PATTERN/.


$ perl -MO=Deparse -e 'print split ".+"'
print split(/.+/, $_, 0);

$ perl -wle 'print split "+"'
Quantifier follows nothing in regex; marked by <-- HERE in m/+ <-- HERE
/ at -e line 1.

$ perl -wle 'print split /+/'
Quantifier follows nothing in regex; marked by <-- HERE in m/+ <-- HERE
/ at -e line 1.

$ perl -wle 'print split qr/+/'
Quantifier follows nothing in regex; marked by <-- HERE in m/+ <-- HERE
/ at -e line 1.

--
Affijn, Ruud

"Gewoon is een tijger."


.

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