Re^2: Reading files n lines a time

Perhaps marginally nicer, the kite operator:

while(( my @lines = map ~~<>, 1 .. 4 )[0]) {
    print @lines;
    print "\n";
}
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perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

Comment on Re^2: Reading files n lines a time Download Code

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Re^3: Reading files n lines a time by mbethke (Hermit) on Dec 06, 2012 at 15:37 UTC
Considering the OP deals with multi-GB files I'd prefer the slightly uglier assignment to `$_` because the kite's tail is not optimized away so all the strings would actually be shoved through the binary negation twice. I was surprised by the result BTW when I looked at the optree; I'm almost completely clueless about what Perl can and cannot optimize but it even a fairly trivial peephole optimizer as in early C compilers could catch this.	[reply] [d/l]

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Re^3: Reading files n lines a time
by mbethke (Hermit) on Dec 06, 2012 at 15:37 UTC

Considering the OP deals with multi-GB files I'd prefer the slightly uglier assignment to $_ because the kite's tail is not optimized away so all the strings would actually be shoved through the binary negation twice.

I was surprised by the result BTW when I looked at the optree; I'm almost completely clueless about what Perl can and cannot optimize but it even a fairly trivial peephole optimizer as in early C compilers could catch this.

[reply]
[d/l]