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Re: what type $in,$out and $err is

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From:
Brandon Allbery
Date:
October 28, 2018 22:00
Subject:
Re: what type $in,$out and $err is
Message ID:
CAKFCL4WMebMvi1_6QUcNfFsfhMcOcZaCWiMnB2Vkb_T_JxXALA@mail.gmail.com
It takes Any — and quite a few more things than are currently documented,
like IIRC filenames, and looks at the actual type passed to decide what to
do with it.

On Sun, Oct 28, 2018 at 3:31 PM Xiao Yafeng <xyf.xiao@gmail.com> wrote:

> I'm curious about what type of $in is on Proc class. As described in
> perl6doc:
> $in, $out and $err are the three standard streams of the
> to-be-launched program, and default to "-" meaning they inherit the
> stream from the parent process. Setting one (or more) of them to True
> makes the stream available as an IO::Pipe object of the same name,
> like for example $proc.out.
>
> I mean, if $in is IO::Pipe object, how can I pass it True?
>
> > my IO::Pipe $bb = True;
> Type check failed in assignment to $bb; expected IO::Pipe but got Bool
> (Bool::True)
>   in block <unit> at <unknown file> line 4
>
> I'm interested in the underlying mechanics of  it. Please enlighten me.
>
> Besides, just curious, why choose '_' as default it looks strange....
>


-- 
brandon s allbery kf8nh
allbery.b@gmail.com

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