Comment by mkl | Hacker News Reader

Comment by mkl | Hacker News Reader

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> Do the "contains" example with 5 terms.

  rg foo1 | rg foo2 | rg foo3 | rg foo4 | rg foo5

or, if filename matches are a possibility

  rg foo1 | rg :.\*foo2 | rg :.\*foo3 | rg :.\*foo4 | rg :.\*foo5

vs

  rak '{.contains("foo1") && .contains("foo2") && .contains("foo3") && .contains("foo4") && .contains("foo5")}'

My point is that despite their claim of superiority, their examples do not show any. Maybe there's a more efficient rak way to do that chain of .contains? Why not demonstrate that?

$ rak '{.contains: "foo1" & "foo2" & "foo3" & "foo4" &"foo5"}'

This actually shows one of the secret powers of the Raku Programming Language: Junctions https://docs.raku.org/type/Junction

Alternately one could express this as:

$ rak '{.contains: <foo1 foo2 foo3 foo4 foo5>.all}'

Or using whatever currying: https://docs.raku.org/type/Whatever

$ rak '*.contains: <foo1 foo2 foo3 foo4 foo5>.all'

I haven't tried this in Rak proper, but based on my understanding of the README you can do something like the following:

    rak '{so one ["foo1", "foo2", "foo3"].map(-> \x{$_.contains(x)})}'

That's a bit though; it'll match lines that contain exactly one of "foo1", "foo2", "foo3", but not zero or 2+.

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